The relationship between inferential confusion, obsessive compulsiveness, schizotypy and dissociation in a non-

clinical sample.

Nakita O’Leary

Submitted for the Degree of

Doctor of Psychology(Clinical Psychology)

School of PsychologyFaculty of Arts and Human Sciences

University of SurreyGuildford, SurreyUnited Kingdom

October 2015

1

Abstract

Objective: Inferential confusion is a reasoning process that has been

theoretically and empirically linked to obsessive-compulsiveness in the

literature. Little is known about the mechanisms by which some people

become more or less inferentially confused and in what contexts. Dissociation

has been postulated as a process related to inferential confusion, yet findings

to date are limited and have been inconclusive. There is preliminary evidence

to support the notion that inferential confusion may also be relevant in other

belief disorders such as delusional disorder but this has not received much

empirical attention. The current study aimed to investigate the relationship

between inferential confusion, obsessive-compulsiveness, dissociation and

schizotypy in a non-clinical sample. Design: Participants (n=107) from the

general population took part in a within-participants experimental study,

designed to assess the propensity to experience inferential confusion in

obsessive-compulsive and delusion-relevant situations and in a threat-neutral

situation. Participants also completed self-report measures of inferential

confusion, obsessive-compulsiveness, dissociation and schizotypy. Results:

As expected, inferential confusion, obsessive-compulsiveness, dissociation

and schizotypy were all significantly positively correlated with each other.

Propensity to experience inferential confusion was only related to measures of

inferential confusion, obsessive-compulsiveness, schizotypy, and dissociation

in the context of the delusion-relevant scenario. Conclusions: There is little

evidence linking measures of obsessive-compulsiveness, dissociation and

schizotypy with experimental measures of inferential confusion. However,

there is evidence that these measures relate to self-report measures of

2

inferential confusion. The implications of this are discussed in terms of

understanding inferential confusion as a process. However, an alternative

explanation for the findings lies in the critique of the methodology of the

experimental task. Inferential confusion still requires experimental

investigation that can be replicated.

3

Acknowledgements

My deepest thanks and appreciation goes to my Major Research

Project supervisor, Dr Laura Simonds, for her constant and consistent support

and guidance in the design, implementation and write up of my Major

Research Project. I would also like to thank Andrew Barnes for his practical

help with creating the study and with using the online programme that runs it.

I would like to show my appreciation to the service users who consulted on

my project during the design phase and the ethics committee for ensuring that

my project was ethically sound. In addition, I express my gratitude to all of the

participants who voluntarily took part in the study without direct or immediate

reward.

I would like to thank Dr Simon Draycott for supervising the

implementation and write up of my Service Related Research Project. I would

also like to thank Nicolette De Villiers for supervising the design of the

project and for her help raising awareness of the survey amongst potential

participants. I would like to give thanks to all the clinical psychologists who

participated in the survey and to Andrew Barnes again for his support in

creating the online programme that the survey was delivered on.

I have appreciated the support of my clinical tutor Dr Vikky Petch and

my honorary clinical tutor Dr Heidi Adshead throughout all of my clinical

placements. I am thankful for their guidance, encouragement and support. I am

also thankful to all of my clinical placement supervisors, as I have learnt so

much from each of them and they have all contributed to my personal and

professional development as a clinical psychologist. I will hold them all in

4

mind as well as the other professionals that I have worked with and learnt

from on my clinical placements.

I would like to extend my thanks to the academic team for providing

me with such a challenging, relevant and innovative learning experience. I

have particularly valued the emphasis on feedback and how this has constantly

been listened to and acted on. My greatest thanks goes to Charlotte King for

always going above and beyond to provide the administrative support that all

trainee clinical psychologists need. Finally, I would like to thank cohort 41 for

sharing this experience of growth and self-development with me, as well as

my friends and family for supporting me through this journey, during both the

good times and the bad times.

5

Contents

Major Research Project Empirical Paper 7

Major Research Project Proposal 103

Major Research Project Literature Review 121

A Brief Overview of Clinical Placements 164

Table of Title of all Academic Assignments 167

6

The relationship between inferential confusion,

obsessive compulsiveness, schizotypy and dissociation

in a non-clinical sample.

Major research project: Empirical paper.

By

Nakita O’Leary

Submitted: April 2015

Word Count: 9,277

7

Abstract

Objective: Inferential confusion is a reasoning process that has been

theoretically and empirically linked to obsessive-compulsiveness in the

literature. Little is known about the mechanisms by which some people

become more or less inferentially confused and in what contexts. Dissociation

has been postulated as a process related to inferential confusion, yet findings

to date are limited and have been inconclusive. There is preliminary evidence

to support the notion that inferential confusion may also be relevant in other

belief disorders such as delusional disorder but this has not received much

empirical attention. The current study aimed to investigate the relationship

between inferential confusion, obsessive-compulsiveness, dissociation and

schizotypy in a non-clinical sample. Design: Participants (n=107) from the

general population took part in a within-participants experimental study,

designed to assess the propensity to experience inferential confusion in

obsessive-compulsive and delusion-relevant situations and in a threat-neutral

situation. Participants also completed self-report measures of inferential

confusion, obsessive-compulsiveness, dissociation and schizotypy. Results:

As expected, inferential confusion, obsessive-compulsiveness, dissociation

and schizotypy were all significantly positively correlated with each other.

Propensity to experience inferential confusion was only related to measures of

inferential confusion, obsessive-compulsiveness, schizotypy, and dissociation

in the context of the delusion-relevant scenario. Conclusions: There is little

evidence linking measures of obsessive-compulsiveness, dissociation and

schizotypy with experimental measures of inferential confusion. However,

there is evidence that these measures relate to self-report measures of

8

inferential confusion. The implications of this are discussed in terms of

understanding inferential confusion as a process. However, an alternative

explanation for the findings lies in the critique of the methodology of the

experimental task. Inferential confusion still requires experimental

investigation that can be replicated.

Keywords

Inferential confusion, Obsessive-compulsiveness, Obsessive-compulsive

disorder, Schizotypy, Dissociation, Delusional disorder

Statement of Journal Choice

This paper presents research on inferential confusion, which has previously

been linked in the literature to obsessive-compulsiveness. It also includes the

study of other related phenomena i.e. dissociation and schizotypy. For these

reasons, the Journal of Obsessive-Compulsive and Related Disorders is the

target journal for this paper. This international journal has an impact factor of

0.812 and publishes high quality research from studies with both clinical and

non-clinical samples. The journal’s broad focus allows for the inclusion of the

novel area in which the current study investigates.

9

Introduction

O’Connor, Aardema and Pelissier (2005) developed a novel theory of

reasoning, termed Inferential Confusion (IC), based upon observation of

individuals diagnosed with obsessive-compulsive disorder (OCD) and over-

valued ideas (OVI). OCD is characterised by the presence of obsessions

(persistent and recurrent thoughts, impulses or images that cause distress)

and/or compulsions (mental strategies or overt behaviours that are aimed at

reducing distress) that are perceived by the individual as either distressing,

time consuming or disruptive to functioning (DSM V, 2014). Obsessions often

involve fears that have a remote basis in reality or, at least, might be

considered implausible by others and involve strategies (i.e. compulsions) that

are unconnected to the obsession or are clearly excessive (e.g. checking a tap

multiple times). OVI have been conceptualised as a variant of obsessive-

compulsiveness (OC) defined as near delusional beliefs (DSM V, 2014)

because they lack the criterion of ego-dystonicity that applies to OCD. In

inferential confusion theory, it is proposed that the persistent doubt evident in

OCD and OVI is the result of a faulty reasoning style that privileges

hypothetical possibilities over reality (O’Connor et al., 2005).

O’Connor and Rollibard (1995) theorized that mental intrusions in

OCD were primary inferences of doubt about reality that led the individual to

distrust their physical senses in preference of an imaginary possibility. An

example of a primary inference of doubt would be thinking that one has left

the cooker on. Subsequent compulsions fail to overcome the primary inference

given that the individual is attempting to use reality to modify an imaginary

possibility. Therefore, a compulsion to check that the cooker is off will

10

inevitably be unsuccessful in resolving doubt about the state of the cooker

because the doubt is imagined; instead, this process only reinforces the doubt

and the cycle of unusual reasoning continues (O’Connor & Aardema, 2003).

In light of these observations, O’Connor et al. (2005) developed the

Inference Based Approach to treatment (IBA). The treatment aims to modify

the inference process and therefore the narrative preluding the primary

inference of doubt (mental intrusion). The IBA has been tested empirically

against Cognitive Behavioural Therapy (CBT), since this is the most

commonly prescribed psychological therapy for OCD. In support of the

relevance of inferential confusion in OCD, Aardema, Emmelkamp and

O'Connor (2005) found that a reduction in obsessive-compulsive symptoms

during a course of CBT coincided with a reduction in inferential confusion.

The IBA has been supported by studies that found it significantly reduces

obsessive-compulsive symptoms (Aardema, Wu, Careau, O’Connor, Julien &

Dennie, 2010). In addition to this, O’Connor, Koszegi, Aardema, van Niekerk

and Taillon (2009) conducted a randomized controlled trial to demonstrate the

effectiveness of IBA in reducing obsessive-compulsive symptoms compared

to behavioural and cognitive-behavioural approaches. In this trial IBA was

found to be superior at reducing obsessive-compulsive symptoms when

compared to other approaches across a range of particular obsessive-

compulsive presentations.

However, whilst Aardema and O’Connor (2012) found that the IBA

produced significant reductions in inferential confusion, obsessionality and

negative mood states, while making significant improvements in the ability to

resolve doubt, a quarter of their participants who could not resolve doubt at the

11

beginning of treatment still could not resolve it at the end. This indicated that

the IBA was not universally effective in resolving doubt. In spite of this,

participants’ symptoms still reduced, suggesting that the IBA can produce

improvement in obsessive-compulsive symptoms even when participants

cannot resolve doubt. This implies that the IBA might also be used as a

general treatment model for distressing symptoms in other thought disorders

that do not necessarily involve the initial doubting process outlined by the

authors of inferential confusion theory. If this were so, it would be reasonable

to deduce that inferential confusion may relate to thought disorders other than

that of OCD or OCD and OVI, such as delusional disorder.

The self-report Inferential Confusion Questionnaire (ICQ; Aardema,

O'Connor, Emmelkamp, Marchand & Todorov, 2005) was developed to

operationalise inferential confusion in empirical studies. High scores on the

measure indicate a reasoning process in which the person recognises their

imagination as a source of inference and acts on the possibility of threat

despite evidence to suggest that no threat exists (O’Connor, Aardema &

Pelissier, 2005). Scores on the ICQ have been found to correlate significantly

with scores on measures of obsessive-compulsiveness in a non-clinical sample

(Aardema, Radomsky, O'Connor & Julien 2008). In a clinical population,

Aardema, O'Connor and Emmelkamp (2006) found that while controlling for

the three domains of the Obsessive Beliefs Questionnaire-44 (OBQ-44;

Obsessive Compulsive Cognitions Working Group, 2005) the relationship

between scores on obsessive-compulsive symptom measures and the ICQ

remained significant (r= 0.43), suggesting that inferential confusion

12

contributes to obsessive-compulsive symptoms independent of obsessive-

compulsive beliefs.

Aardema et al. (2010) subsequently extended the ICQ to include

consideration of an over-reliance on possibility during reasoning; absorption

into imaginary sequences; category errors; irrelevant associations; selective

use of out-of-context facts and apparently comparable events; as well as the

original inverse inference and distrust of senses components of inferential

confusion. The researchers considered these additions to be central facets to

the reasoning process involved in inferential confusion. The new measure,

ICQ-EV (extended version), showed good convergent validity with strong

relationships with measures of obsessive-compulsive symptoms in all samples

when other cognitive domains and general distress were controlled for.

To further investigate inferential confusion, Aardema, O'Connor,

Pélissier and Lavoie (2009) developed a novel experimental paradigm – the

Inference Process Task (IPT) - and compared participants with a diagnosis of

OCD to a non-clinical control group. The IPT is a reasoning task that presents

participants with ambiguous situations (e.g. a situation in which it is unclear

whether there has been a car accident). The IPT involves asking participants

to estimate the probability that an accident has happened. After this,

information is presented that is intended to either reduce doubt (‘reality-based

information’) or to increase it (‘possibility-based information’). The IPT was

designed to emulate the dynamic process of reasoning observed in OCD in

which hypothetical possibilities overturn evidence of the senses (i.e. reality).

As predicted, Aardema et al. (2009) found that the influence of possibility-

based information on doubt was higher in those with OCD than in a non-

13

clinical control group. There was also a strong positive relationship between

the levels of doubt in the IPT and obsessive-compulsive symptom severity.

In spite of the positive findings linking inferential confusion and

obsessive-compulsiveness, there remains a lack of understanding as to why

people with OCD might be more susceptible to the impact of possibility-based

information, or why it is that some people become so absorbed into imaginary

states that the possibility of what might be there overrides their perception of

what is there. In the case of the latter, O’Connor and Aardema (2012) propose

that the reasoning process of inferential confusion may be related to

dissociative absorption. They suggest that by making inferences about possible

states of affairs, the individual is likely to feel a sense of dissociation between

the world their senses perceive and the world inferential confusion has led

them to understand. In support of this, Aardema and Wu (2011) found that the

absorption subscale of the Dissociative Experiences Scale (DES-II, Carlson &

Putnam, 1993) was significantly positively correlated with inferential

confusion (r=.53). This finding suggests that dissociative absorption may be

similar to, or play a role in, the “immersion in possible worlds” that O’Connor

and Aardema (2012) describe as characteristic of inferential confusion.

As noted by Morrison (2014), the literature shows inconsistent results

from studies investigating the relationship between OC and dissociation.

Inferential Confusion theory indicates that, although people with OCD can

perceive reality accurately, they do not integrate this information effectively

into reasoning. This, Morrison (2014) observed, is similar to the lack of

integration noted in dissociation by Van Ijzendoorn and Schuengel (1996).

Van Ijzendoorn and Schuengel (1996) highlight the disruption of usually

14

integrated functions of consciousness, identity, memory and perception of

one’s environment as an essential feature of dissociation. Morrison (2014)

replicated Aardema et al.’s (2009) experimental paradigm in order to explore

the relationship between dissociation and susceptibility to possibility-based

information, in those high and low in obsessive-compulsiveness.

Unexpectedly, Morrison (2014) did not find a relationship between

dissociation and participant’s level of inferential confusion, and neither was

there evidence of a relationship between inferential confusion and obsessive-

compulsiveness. However, Morrison (2014) argued that these findings could

not be interpreted as definitive evidence that there was no relationship

between inferential confusion and dissociation since they were based on a

single novel study and, furthermore, a competing explanation might be the

lack of validity of the IPT. That is, at that time, the IPT task had not been

replicated outside the team who had devised the task and, Morrison (2014)

argued, it was plausible that the paradigm may not measure inferential

confusion in the way it claims to. Morrison (2014) did not utilise a self-report

measure of inferential confusion to provide validity for the IPT data.

Therefore, one principal aim of the current study was to replicate Morrison’s

(2014) use of Aardema et al.’s (2009) paradigm, with the addition of the ICQ-

EV (Aardema et al., 2010) to measure inferential confusion alongside the

experimental IPT. The intention was to explore whether lack of IPT validity

might have contributed to the null results found by Morrison (2014) regarding

the relationship between inferential confusion and dissociation and obsessive-

compulsiveness.

15

The current study also extended the IPT to consider a delusion-relevant

situation. Evidence indicates that inferential confusion is higher in participants

with OCD than in those with other anxiety diagnoses but that it is equally high

in participants with delusional disorder (DD; Aardema et al., 2005). Delusions

are defined as false beliefs despite evidence to the contrary (DSM V, 2014).

Claridge, McCreery, Mason, Bentall, Boyle, Slade and Popplewell (1996)

used the term schizotypy to denote non-clinical delusional type beliefs that lie

on a continuum with delusions in clinical populations. When considering

obsessive-compulsiveness and delusions (or schizotypy to refer to the non-

clinical terminology) together, the current study defines them both as unusual

ways of thinking about reality, that are not shared by others, that are causally

implausible and which lie on a continuum of severity. Proponents of

inferential confusion suggest that, like DD, OCD is a belief disorder and that

inferential confusion might underpin both presentations. This, and the

empirical evidence cited, suggests the IPT (which currently only focuses on an

OCD-relevant and a neutral situation) might be usefully extended by including

a delusion-relevant scenario in order to assess inferential confusion processes

in that context. In addition, Aardema at al. (2009) suggested that their study

would benefit from replication with the addition of more pairs of reality- and

possibility-based information (three pairs are used in the original paradigm)

and more hypothetical scenarios. The current study follows up these

recommendations, extending the current IPT in these ways.

In summary, the current state of knowledge highlights inferential

confusion as a reasoning process that is likely involved in obsessive-

compulsiveness. Given the largely correlational nature of the current evidence

16

to support these claims, more experimental work is needed. Morrison (2014) is

the only study to date to replicate the IPT paradigm outside of the research

group that devised it. Morrison was unable to support the main predictions

arising from inferential confusion theory and was unable to support the novel

hypothesis that the tendency to dissociate was related to inferential confusion.

Furthermore, whilst there is preliminary evidence to suggest that delusional

experiences are related to inferential confusion (Aardema et al., 2005), to date,

there are no experimental studies that assess inferential confusion in the

context of both obsessive-compulsiveness and delusions. Therefore, the aim of

the current study was to extend the IPT paradigm to measure inferential

confusion in the context of both obsessive-compulsiveness and delusions and

to assess the relationship between inferential confusion, obsessive-

compulsiveness, dissociation and schizotypy (i.e. non-clinical delusion-

proneness) in a non-clinical sample. A non-clinical sample was used since

obsessive-compulsiveness and schizotypy are considered to be phenomena

experienced by the general population to different degrees (Gibbs, 1996; Johns

& Os, 2001). Therefore, the intensity of these phenomena can be measured on

a continuum rather than with distinct categorical criteria. In addition,

transdiagnostic models of clinical problems focus on how phenomena might

underpin multiple psychological problems. In the context of these models, this

research moves away from studying diagnostic categories per se towards

studying the underlying cognitive processes involved in a range of

presentations.

17

In the current study, it was hypothesised that:

(1) Following from Aardema et al. (2009), possibility-based information

presented after each imagined scenario will increase participants’ self-reported

level of doubt, whereas reality-based information presented after each

imagined scenario will reduce participants’ self-reported level of doubt.

(2) Participants who score higher on the ICQ-EV will report significantly

higher levels of doubt in response to the possibility-based information in all

three scenarios presented to them in the IPT task.

(3) Doubt as a result of possibility-based information will be positively

correlated with obsessive-compulsiveness and this effect will be strongest for

the OC-related scenario of the IPT. Doubt as a result of possibility-based

information will be positively correlated with schizotypy, and this effect will

be strongest in the delusion-related scenario of the IPT.

(4) Frequency of dissociative experiences will be positively correlated with

inferential confusion as operationalized by self-report (ICQ-EV) and

experimental (IPT) measures.

Method

Overview of design

Experimental Design: The study used a within-participants

experimental design. The independent variable ‘scenario type’ had three

levels: OC-relevant (hitting a pedestrian when driving), delusion-relevant

(being followed by another car) and neutral (a bus strike). The independent

variable ‘information type’ had two levels: reality and possibility-based

information. The dependant variable was the level of doubt experienced by

18

participants. This was operationalized by the participants’ reports of perceived

probability that the inferred event in each scenario had occurred. Similar to

Aardema et al.’s (2009) study, higher probability scores indicated a greater

level of doubt with regards to the idea that the incident had not occurred. Self-

report measures were also completed by participants to assess levels of

inferential confusion, obsessive-compulsiveness, dissociation and schizotypy.

The study was designed for remote completion using Qualtrics survey

software, hosted at the University of Surrey.

Participants

Participants were recruited from the general population in a non-

clinical setting. A diagnosis of OCD or delusional disorder was not an

inclusion criterion since obsessive-compulsiveness, dissociation and

schizotypy are construed as continuous variables in the general population.

Variability in these measures would be expected in a non-clinical sample.

Participants who scored above the cut off for clinical significance on the OCI

were not excluded from the study, despite the sample being intended to

represent a non-clinical population. This was because the OCI is not a

clinically recognised diagnostic tool and therefore cannot determine whether

participants’ are considered clinical or non-clinical in their presentations. The

study was designed to be completed by participants aged 16 and older,

allowing them to give independent informed consent. However, as the study

was completed remotely, it was not possible to verify participant age. The

study was advertised on websites that promote psychological studies online

and via social networking sites. Snowball sampling was also utilised in that

19

participants were asked to share the online study advertisement with others

connected to their social network.

An a priori sample size calculation based on correlation analysis

indicated a sample size of 100 would be sufficient to detect a moderate effect

size of r =.3 at 80% power for a two tailed hypothesis (alpha .05). 206

participants started the online study. There was a 51.94% completion rate with

107 participants submitting complete data. The sample was therefore sufficient

to detect at least moderate effect sizes. Participant characteristics are reported

in the Results section.

Measures

The Inference Process Task (IPT): This followed the design used by

Aardema et al. (2009) and Morrison (2014). The basic design of the IPT

involves the following stages: (1) an ambiguous scenario is presented; (2) the

participant rates how anxious they would feel should the incident implied by

the scenario really occur; (3) the participant rates the probability that the

implied incident has occurred; (4) the participant is presented with pairs of

reality and possibility based information designed to influence doubt about the

incident. After each piece of information, the participant re-rates the

probability that the incident implied occurred. These stages will now be

described below indicating how the current study extended the paradigm

utilised by Aardema et al. (2009) and Morrison (2014). All materials for the

IPT can be seen in Appendix B.

(1) In Aardema et al. (2009) and Morrison (2014), two written

vignettes were given to participants. The OC-relevant scenario was designed

20

to emulate a common concern in OCD (hitting a pedestrian whilst driving).

Abramowitz, Taylor and McKay (2009) reported this experience to be one out

of the five main dimensions of obsessions and compulsions seen in OCD. The

non-OC-relevant scenario (a bus strike) was designed to be the neutral (i.e.

non-threat) condition. Aardema et al. (2009) explained that inferential

confusion is only expected in relation to threat-laden information. Therefore

the neutral scenario acts as a control condition. The additional scenario

devised for this study was designed to emulate a common concern in

delusional disorder (being persecuted by others). Bell, Halligan and Ellis

(2006) report this to be common theme for people experiencing clinical

delusions. The delusions-relevant scenario was designed to replicate the

structure of the OC-relevant scenario. It used the activity of driving a car to

keep the scenarios as similar as possible. In the delusion-relevant scenario,

instead of the inferred event regarding the participant hitting a pedestrian with

their car, it was regarded them being followed by people that wanted to steal

their car.

(2) The initial anxiety rating question in all three scenarios was: ‘How

anxious would you feel in the above situation?’ measured on a scale of 0 to 10.

(3) The initial probability rating question required participants’ to rate

the probability that an event had occurred in each of the three ambiguous

situations presented to them. This was taken to represent participants’ level of

doubt that the event had not happened, which was interpreted as their

propensity to experience inferential confusion. For example, in the OC-

relevant scenario, the probability rating question was: ‘What do you consider

the probability that an accident has happened under these circumstances?’

21

measured on a scale of 10 – 100%. A scale of 10 to 100 as opposed to 0 to 100

was used for the probability rating, since a score of zero would negate the

assumed probability that something had occurred altogether.

(4) Different pieces of information about the scenario are then

introduced. ’Reality-based information’ aims to reduce doubt by referring to

the senses. In the OC-relevant scenario, an example of this is, ‘you turn your

head and see no one lying on the street’. In contrast ‘possibility-based

information’ aims to increase doubt by referring to hypothetical situations. In

the OC-relevant scenario, an example of this is, ‘you may not have seen

anything because it is quite crowded’. These pieces of information were

presented as pairs (Table 1); each pair consisted of a reality-based piece of

information and a possibility-based piece of information. This was in order to

mimic the dynamic doubting process seen in OCD (Aardema et al., 2009).

Aardema et al. (2009) calculated two variables from this data representing the

overall impact of each different type of information (known as the cumulative

impact of reality and possibility-based information). The current study

included a further pair of reality and possibility-based piece of information to

the OC-relevant and neutral scenario, to investigate whether this relationship

continued to strengthen, as would be expected given the persistent nature of

obsessional doubt (Aardema et al., 2009). New reality and possibility-based

pairs of information were created for the delusion-relevant scenario, which

attempted to replicate the style of the OC-relevant and non-OC-relevant pairs

of reality and possibility-based information from Aardema et al.’s (2009) and

Morrison’s (2014) studies. The pieces of information were designed to either

22

sustain doubt about whether an inferred event had occurred (possibility-based)

or challenge the idea that the event had occurred at all (reality-based).

TABLE 1. Pairs of reality and possibility-based information for the OC-

relevant, delusion-relevant and neutral scenarios for the current study.

OC relevant scenario Non-OC relevant scenario

Delusions relevant scenario

R1 “You look in the rear-view mirror and see a pothole in the road.”

“At the end of the street you see a bus driving on what appears to be a different route.”

“The expressions on the men’s faces in the car are not menacing or threatening in anyway.’

P1 “The pothole may not have been deep enough to cause the bump.”

“Maybe the bus was out of service since you could not see whether there were any people in it.”

“The lack of expression in their faces may be because they want to take you by surprise.”

R2 “You turn your head and see no one lying on the street.”

“A person tells you he took the bus earlier in the day.”

“It is not very busy and you are in a much safer place for the car to overtake you now than at other points in the journey.”

P2 “You may not have seen everything, because it’s quite crowded.”

“The strike may have only started later in the day.”

“Other cars have overtaken you and the car behind at other points in your journey.”

R3 “You watch the expressions on people’s faces and see no emotion that might indicate an accident.”

“You call the information service and get an auto- mated message with no mention of any strike.”

“The number plate indicates that the drivers are from a country where they drive on the other side of the road.”

P3 “The lack of expression in people’s faces may have been shock.”

“Maybe the bus company doesn’t give out this type of information that quickly.”

“The drivers have managed to stay on the correct side of the road for the whole journey up until this point.”

R4 “The car behind you did not stop as you would expect had there been an accident.”

“The bus you want to get has been late a lot recently due to there having been roads works on its route.”

“You realise that you are driving way below the speed limit.”

P4 “Perhaps the driver of the car behind you did not see what had happened either because it was so busy.”

“The road works were expected to have finished by now.”

“You have been driving below the speed limit at other points in the journey and the car has not overtaken you.”

Self-report measures: The Inferential Confusion Questionnaire (ICQ-

EV) (Aardema et al., 2010) is a 30-item measure in which each statement is

rated on a 6-point scale from 1: ’strongly disagree’, to 6: ‘strongly agree’. This

gives a total score ranging from 30 to 180. The ICQ-EV measures

23

subcomponents of inferential confusion such as inverse inference, a tendency

to distrust the senses and an over- reliance on possibility during reasoning,

absorption into imaginary sequences, category errors, irrelevant associations,

selective use of out-of-context facts and apparently comparable events. A total

score is derived. High scores on this measure indicate a greater tendency for

the individual to experience inferential confusion-characteristic reasoning

processes. Internal reliability (Cronbachs’s alpha) in the current sample

was .962 indicating excellent reliability.

Dissociative Experiences Scale-II (DES-II; Carlson & Putnam, 1993)

is a 28-item self-report questionnaire. Each item is rated on a scale from 0%

‘never happens to me’ to 100% ‘always happens to me’. To estimate a total

score that is interpretable on a percentage scale, the sum of the item scores is

divided by 28 to achieve a score ranging from 0 to 100. Dissociation is

operationalized here as experiences of memory loss, depersonalisation,

derealisation and absorption into the imaginary. Higher scores on this measure

indicate that the individual has dissociative experiences more frequently than

individuals with lower scores. Internal reliability (Cronbachs’s alpha) in the

current sample was .961 indicating excellent reliability.

Obsessive Compulsive Inventory - Revised (OCI-R; Foa, Huppert,

Leiberg, Langner, Kichic, Hajcak & Salkovskis, 2002) is an 18-item self-

report measure of obsessive-compulsiveness. The intensity of obsessive-

compulsiveness experiences is rated on a 5-point scale ranging from 0 ‘not at

all’ to 4 ‘extremely’. The total score on this measure can range from 0 to 72.

The OCI-R provides an overall indication of obsessive-compulsiveness related

distress as well as subscale scores for checking, doubting, ordering,

24

obsessions, hoarding and neutralising although only the total score was used in

this study. High scores on this measure indicate a greater intensity of

obsessive-compulsiveness experiences. Internal reliability (Cronbachs’s alpha)

in the current sample was .896 indicating very good reliability.

The Magical Ideation Scale (MIS; Eckblad & Chapman, 1983) is a 30-

item true-false measure of magical ideation, which is a symptom of

schizotypy. Items rated true are scored 1 and false items scored 0 resulting in a

total score ranging from 0 to 30. It identifies whether an individual has

paranormal and delusion-like beliefs about subjects such as telepathy,

astrology, conspiracy theories and UFO’s. High scores on this measure

indicate symptoms suggestive of a predisposition to psychosis. Internal

reliability (Cronbachs’s alpha) in the current sample was .85 indicating very

good reliability. All measures used in the study can be seen in Appendix B.

Apparatus

The online survey was created using Qualtrics software. The software

was set such that each participant received the scenarios in randomized order.

This software presented all the measures included in the study to each

individual participant. The Qualtrics programme recorded all participants’

responses. These were then downloaded from Qualtrics into an SPSS data file.

IBM SPSS statistics 22 was used to manage and analyse the data.

Procedure

The study was advertised on social media websites and on the

psychology testing website ‘Psychological Research on the Net’. This site was

25

located via another researcher who had recommended it. Participants who had

taken part were asked to send the study link to others in their social network.

Participants accessed the study by clicking a link embedded within the study

advert. The information screen that initially appeared orientated participants to

the study. An informed consent screen was also presented which required

participants to actively give consent to participate in the study (Appendix C).

Participants were then directed to demographic questions that they were

required to answer (Appendix D). The IPT was presented next (Appendix A).

The order in which each of the three scenarios included in the task were

presented was randomised and participants had to respond to each and every

question regarding each scenario before they had the ability to continue to the

next element of the study. Participants were then required to complete the

ICQ-EV, DES, OCI-R and the MIS (Appendix B). Finally, the debrief screen

was presented. This informed participants of who to contact should they have

any questions or want a summary of the findings (Appendix C). The debrief

also directed participants to sources of support should the study have brought

up any difficulties for them.

Ethics

This study was reviewed and granted a favourable ethical opinion by

the Faculty of Arts & Human Sciences Ethics Committee at the University of

Surrey prior to data collection (see appendix E for ethics committee letter).

Informed consent: The information sheet presented at the beginning

of the online study informed participants that the purpose of the study was to

26

test the relationship between reasoning processes, beliefs and behaviours.

While this was true information, the type of reasoning process, beliefs and

behaviours were not initially revealed, in order to avoid demand

characteristics. The BPS code of research ethics states that withholding the

exact nature of the study is necessary in experimental designs (BPS Ethics

committee, 2009). This omission of information was not expected to cause any

distress to participants and full details regarding the nature of the research was

revealed in the debrief. This was presented once participants had completed all

parts of the online study. The information sheet also indicated that participants

had a right to withdraw at any time before the survey was completed without

having to give a reason and without consequence. Participants were required

to actively indicate their consent to participate before they could proceed to

the study.

Risk to participants: There was minimal foreseeable risk that

participants may have been disturbed by the nature of the measures and/or the

inference task included in the study. It was considered that any potential stress

caused by this study would have been no greater than would be expected for

participants to experience in their ordinary life. However, to manage potential

upset, relevant sources of information and support were outlined in the

debrief.

Data protection: All information gathered by the online study was

treated as confidential. Data was used and stored in line with the Data

Protection Act 1998, in that it was stored on an online password protected

programme. Participation was anonymous as the online survey did not require

participants to enter any identifiable information. Participants were informed

27

that they would not be identifiable in any publication or presentations that

arose from the study’s results.

Data preparation and analysis

The study data was collected online between September 2014 and

February 2015. The study was set up to force responses, therefore, there was

no missing data to manage. The data were imported into SPSS and prepared

for analysis. This involved checking the responses, calculating total scores and

assessing the distribution of each of the study variables and whether this

suggested use of parametric or non-parametric tests (See Appendix F for

normality plots). Following from Aardema et al.’s (2009) study, the target

dependent variable was cumulative impact of possibility-based information.

The formula that was used to calculate this was (P1-R1) + (P2-R2) + (P3-R3)

+ (P4-R4) with P meaning probability-based and R meaning reality based

piece of information and the numbers referring to at what time point each

piece of information was presented. This formula calculated the changes in

levels of doubt that were directly influenced by the possibility-based

information across the four time points measured. The formula used for

cumulative impact of reality-based information was -1 x ((R1 – B) + (R2 – P1)

+ (R3 – P2) + (R4 – P3)) with B representing the baseline level of doubt

measured by the initial probability question. This formula calculated the

changes in level of doubt that were a direct impact of reality-based

information across the four time points. A positive value was obtained due to

the use of -1.

28

Results

The overall sample consisted of 107 participants, aged between 15 and

73 years old with a mean age of 28.73 years (SD 11.43). While the research

was designed for adults who could give their own consent, there was no way

to prevent younger adults taking part in the online study, nor was there a way

to be certain of the veracity of anyone’s self-reported age. The majority of

participants were White British (43.9%), and most were single/never married

(61.7%). 48.6% were employed for wages and (29.0%) were educated to

Bachelor degree level. More participants reported being of no religion (43.9%)

and half of participants completed the study from the UK (50.5%). See

Appendix G for full table of demographics of the overall sample.

TABLE 2. Distribution of total scores on questionnaire measures for

whole sample.

Questionnaire measures

Mean SD Possible score range

Score range in sample

ICQ-EV 83.95 28.56 30 - 180 34 - 164

OCI 14.91 11.18 0 - 72 0 - 51

DES (II) 24.17 19.08 0 - 100 0 - 100

MIS 7.26 5.46 0 - 30 0 - 23

In this sample, the distribution suggests that there was no restricted

range on any of the measures, meaning that a wide spread of scores for each

measure are represented. The mean scores are as might be expected for a non-

29

clinical sample, suggesting that the sampling strategy was effective. In

comparison to Aardema et al.’s (2009) non-clinical sample, the inferential

confusion mean in this sample is much higher. However, this is likely due to

Aardema et al. (2009) having used the ICQ containing 5 scale points, as

opposed to the current study, which used the ICQ-EV, containing 6 scale

points.

The distribution of scores in this sample on the IPT variables (Table 3)

suggests that there were no restricted ranges. The average score for initial

anxiety rating was twice as high in the OC-relevant scenario than the neutral

scenario. This supports the concept that the OC-relevant scenario is threat

laden. The delusion-relevant scenario mean initial anxiety rating was midway

between the other two scenarios, suggesting that it did imply more threat than

the neutral scenario, but not to the extent of the OC-relevant scenario. The

baseline probability scores were higher in the OC-relevant and neutral

scenarios than in the delusion-relevant scenario, suggesting that there may

have been less doubt induced by this scenario than the other two. The impact

of possibility and reality-based information was lower in the delusion-relevant

scenario than in the OC-relevant or neutral scenario, suggesting that, overall,

the desired effect was less pronounced in this scenario of the IPT. The impact

of reality-based information was much higher than the impact of possibility-

based information in all three scenarios.

30

TABLE 3. Descriptive statistics for IPT variables

For the OC-relevant scenario, baseline anxiety and baseline probability

were strongly positively correlated (r = .603, n = 107, p = .001). Baseline

anxiety was also positively correlated with cumulative impact of possibility-

based information (r = .291, n = 107, p = .002) and cumulative impact of

reality-based information (r = .485, n = 107, p = 000). A similar relationship

was found between baseline anxiety and baseline probability in the delusion-

31

IPT Mean SD Score range in sample

OC-relevant scenario

Initial anxiety (0-10)

8.82 1.88 0 - 10

Baseline probability (10-100)

73.60 24.26 10 - 100

Cumulative Impact of probability-based information

35.46 45.94 -73 – 185

Cumulative Impact of reality-based information

81.19 52.38 -44 - 196

Delusion-relevant scenario

Initial anxiety (0-10)

6.24 2.66 0 - 10

Baseline probability (10-100)

46.41 27.43 10 - 100

Cumulative impact of possibility-based information

14.09 28.66 -35 - 165

Cumulative impact of reality-based information

26.49 33.36 -75 - 175

Neutral scenario Initial anxiety (0-10)

4.04 2.43 0 - 10

Baseline probability (10-100)

65.96 23.99 11 - 100

Cumulative impact of possibility based information

34.75 50.52 -114 - 250

Cumulative impact of reality-based information

62.99 52.42 -74 - 300

relevant scenario although the effect size was stronger (r =.825, n = 107, p

= .000). In this scenario, baseline anxiety also positively correlated with

cumulative impact of possibility-based information (r = .671, n = 107, p

= .000) and reality-based information (r = .467, n = 107, p = .000). These

findings would be expected given that perceived anxiety in a situation is likely

to be associated with higher threat likelihood in that situation.

In contrast, baseline anxiety and baseline probability in the neutral

scenario were not significantly correlated (r = .160, n = 107, p = .100).

Additionally, baseline anxiety did not correlate with cumulative impact of

possibility-based information (r = .151, n = 107, p = .121) or reality-based

information (r = .173, n = 107, p = .075) in this scenario.

Histograms were used to check if all variables were sufficiently

normally distributed. As to be expected from a non-clinical sample, most of

the variables demonstrated a negative skew. This was with the exception of

the ICQ-EV and the cumulative impact of reality-based information in the

OC-relevant scenario, which were both sufficiently normally distributed.

Given this outcome, non-parametric tests were used throughout. (See

Appendix G for histograms).

Hypothesis 1: Following from Aardema et al. (2009), possibility-

based information presented after each imagined scenario will increase

participants’ self-reported level of doubt about the outcome of each scenario,

whereas reality-based information presented after each imagined scenario will

reduce participants’ self-reported level of doubt.

Figure 1 demonstrates how participants’ level of doubt fluctuated over

the different time points in all three scenarios. For all three scenarios, the

32

impact of reality and possibility-based information showed the characteristic

pattern as predicted by inferential confusion theory, with reality-based

information reducing doubt and possibility-based information increasing

doubt. However, there is part of the sequence in the delusion-relevant scenario

where this does not happen. Of note is that the characteristic effect seems to

persist with the inclusion of the additional pair of reality and possibility-based

information. However, it is evident that, in the OC-relevant and neutral

scenarios, doubt at the end of the experiment was much lower than at the start.

For the delusion-relevant scenario, doubt did not reduce as much from start to

finish. This may be because doubt started at a lower point relative to the other

two scenarios.

FIGURE 1: The cumulative impact of possibility and reality-based

information

B R1 P1 R2 P2 R3 P3 R4 P4102030405060708090

100

OC-relevant scenarioDelusions-relevant scenarioNeutral scenario

Reality and Possibility based information points

Patic

ipan

ts' j

udge

men

ts o

f pr

obab

ility

that

infe

rred

in-

cide

nt h

ad o

ccur

red

Hypothesis 2: Participants who score higher on the ICQ-EV will

report significantly higher levels of doubt in response to the possibility-based

information in all three scenarios presented to them in the IPT task.

33

Spearman’s rho correlation was conducted to measure the relationship

between inferential confusion (as measured by the ICQ-EV) and the

cumulative impact of possibility-based information on participants reported

level of doubt in the IPT. No significant relationship was found between the

two variables in either the OC-relevant scenario (r = .158, n = 107, p = .105)

or in the neutral scenario (r =.118, n = 107, p = .227). Conversely, a

significant positive correlation was found between inferential confusion and

the cumulative impact of possibility-based information on participants’ self-

reported doubt in the delusions-relevant scenario with a moderate effect size (r

= .359, n = 107, p = .000). These findings suggest that the two ways of

measuring inferential confusion are correlated only in the delusion-relevant

scenario.

Hypothesis 3: (a) Doubt as a result of possibility-based information

will be positively correlated with obsessive-compulsiveness and this effect

will be strongest for the OC-related scenario of the IPT; (b) doubt as a result

of possibility-based information will be positively correlated with schizotypy,

and this effect will be strongest in the delusion-related scenario of the IPT.

No significant relationship was found between obsessive-

compulsiveness (as measured by the OCI-R) and the cumulative impact of

possibility-based information on participants’ reported levels of doubt in the

OC-relevant scenario (r = .049, n = 107, p = .617) or the neutral scenario (r =

-.048, n = 107, p = .622). A significant positive relationship was found

between obsessive-compulsiveness and the impact of possibility-based

information on participants’ reported levels of doubt in the delusions-related

scenario (r = .320, n = 107, p = .001). Part (a) of the hypothesis was partially

34

supported in that the impact of possibility-based information relates to

obsessive-compulsiveness but only in the delusion-related scenario. However,

there was no correlation between obsessive-compulsiveness and doubt in OC-

related scenario, which was contrary to prediction.

No significant relationship was found between schizotypy (as

measured by the MIS) and the impact of possibility-based information on

participants’ reported levels of doubt in either the OC-relevant scenario (r =

-.014, n = 107, p = .887) or the neutral scenario (r = -.005, n = 107, p = .961).

However there was a significant positive correlation found between

schizotypy and the impact of possibility-based information on participants’

reported level of doubt in the delusion-relevant scenario with a moderate

effect size (r = .281, n = 107, p = .003). Similarly, part (b) of the hypothesis

was mostly supported, given that the impact of possibility-based information

related to schizotypy, but only in the delusion relevant scenario.

Hypothesis 4: Frequency of dissociative experiences will be positively

correlated with inferential confusion as operationalized by (a) self-report

(ICQ-EV) and (b) experimental (IPT) measures.

No significant relationship was found between dissociation (as

measured by the DES II) and the impact of possibility-based information on

participants’ reported levels of doubt in the OC-relevant scenario (r = -.010, n

= 107, p = .917), or the neutral scenario (r = -.040, n = 107, p = .679).

However, a significant positive relationship was found between dissociation

and the impact of possibility-based information on participants’ reported

levels of doubt in the delusion-relevant scenario (r = .252, n = 107, p = .009).

35

In addition, dissociation positively correlated with obsessive-

compulsiveness (r = .543, n = 107, p = .000). Obsessive-compulsiveness

positively correlated with schizotypy (r = .556, n = 107, p = .000) and

schizotypy was correlated with dissociation (r = .548, n = 107, p = .000).

Inferential confusion (as measured by ICQ-EV) also positively correlated with

dissociation (r = .359, n = 107, p = .000), OC (r = .470, n = 107, p = .000)

and schizotypy (r = .361, n = 107, p = .000). These correlations evidence

moderate to large effect sizes in the direction that would be expected.

Discussion

The overall purpose of this study was to derive new information

regarding the relationship between inferential confusion and obsessive-

compulsive, schizotypal and dissociative experiences. The aim was to

replicate and extend the experimental paradigm created by Aardema et al.

(2009) and used by Morrison (2014) to measure the inferential confusion

reasoning process in action, in a non-clinical sample; then to explore the

relationship between inferential confusion and other phenomena that had been

theoretically linked to inferential confusion such as obsessive-compulsiveness

(O’Connor et al., 2005) schizotypy (Aardema et al., 2005) and dissociation

(Aardema & O’Connor, 2012).

The hypotheses proposed were partially supported. The findings

appeared to support the contention that the IPT successfully operationalizes

the dynamic doubting process that is said to characterise obsessive-

compulsiveness. The expected oscillation of levels of doubt in response to

36

reality and possibility-based information were seen in all three scenarios. They

were more pronounced in the original two scenarios of the task designed by

Aardema et al. (2009) (OC-relevant and Neutral) than in the additional

scenario designed to extend the experimental remit of the IPT (delusion-

relevant). These findings suggest there may be something different about the

process of inferential confusion when in the context of a delusion-relevant

scenario, as opposed to the OC-relevant or neutral scenarios. The cumulative

impact of possibility and reality-based information continued to have an effect

with the inclusion of an additional possibility and reality-based information

pair in the current study. This supports Aardema et al’s (2009) hypothesis that

additional possibility and reality-based information will continue to impact the

individual’s reasoning as to whether an event has occurred or not. This is

considered to represent the doubting process seen in obsessive-

compulsiveness, whereby the individual will act in response to what might be

there over what their senses tell them is there. For example, washing ones

hands at the thought of them possibly being dirty, despite being able to see

that they look clean. The reasoning behind this is what O’Connor et al. (2005)

describe as inferential confusion.

In Aardema et al. (2009) and Morrison (2014) the cumulative impact of

possibility-based information on participants’ levels of doubt was taken to

represent inferential confusion in action. However, the current study also used

an empirically tested self-report measure of inferential confusion, which was

found not to correlate with the cumulative impact of possibility-based

information on doubt in the two original scenarios of the IPT. This suggests

that the IPT and the ICQ_EV might not have been measuring the same

37

construct, a possibility raised by Morrison (2014) who failed to replicate

Aardema et al.’s (2009) findings. However, scores on the ICQ_EV did

significantly correlate with the cumulative impact of possibility-based

information on doubt in the delusion-relevant scenario created for the current

study. One explanation for this could be that the delusion-relevant scenario

presented an ambiguous situation (potential car-jacking) that can be assumed

to be quite an unusual experience to the majority of participants. This is in

comparison to the other two scenarios, which may be more familiar to most

participants (potential car accident, potential bus strike). Therefore, the

positive correlation between experimental inferential confusion (i.e. doubt

arising from the delusion scenario) and self-report inferential confusion might

be due to both measures accessing reasoning that is considered unusual. That

is, the reasoning in the car accident and bus scenarios might represent the

essence of inferential confusion less then the delusion-related scenario.

The cumulative impact of possibility-based information on doubt (i.e.

experimentally-induced inferential confusion) was not shown to relate to

obsessive-compulsiveness, schizotypy and dissociation in the two original

scenarios developed by Aardema et al. (2009). This finding is similar to

Morrison (2014) who used only the two original scenarios and measures of

obsessive-compulsiveness and dissociation. However, experimentally-induced

inferential confusion did relate to these measures in the context of the

delusion-relevant scenario. One explanation for this might be that the OC-

relevant scenario is not sufficiently representative of obsessive-compulsive

concerns and, therefore, might not have shown a correlation with the self-

report measure of obsessive-compulsiveness. Therefore results for this

38

scenario were more in line with what was expected from the neutral scenario.

Alternatively, these findings might raise the question of whether inferential

confusion in the context of delusions is more strongly related to schizotypy,

obsessive-compulsiveness and dissociation. While a positive relationship

between cumulative impact of possibility-based information (inferential

confusion as measured by the IPT) and schizotypy was expected (Aardema et

al., 2005), this relationship was hypothesised to be seen in all scenarios and

strongest in the delusion-relevant scenario. A positive relationship between

cumulative impact of possibility-based information (inferential confusion as

measured by the IPT) and obsessive-compulsiveness was also expected

(Aardema et al., 2009) and hypothesised to be present in all scenarios, but

strongest in the OC-relevant scenario. The current findings do not support

these theoretical assertions, although the current study would need replication

before firm conclusions are drawn.

Further complicating the interpretation of the IPT is that inferential

confusion, as measured by the ICQ-EV, was positively correlated with scores

on measures of obsessive-compulsiveness, schizotypy and dissociation. This

further questions whether the IPT, as operationalized through the original

scenarios in Aardema et al. (2009) and self-report ICQ-EV measure different

constructs. It may be that the IPT measures participants’ state of oscillation

between their levels of doubt about whether an inferred event has occurred or

not, whereas the ICQ-EV measures a trait of subjectively reported unusual

experiences. These two components of the inferential confusion theory, as

outlined by Aardema et al. (2009) and Aardema et al. (2010) respectively, may

be too dissimilar to correlate under statistical investigation. If this is the case,

39

the mechanisms by which inferential confusion operates need to be explored

and inferential confusion as a theory needs to be additionally operationalized.

Whilst the findings from the current study are inconsistent with

Aardema et al.’s (2009) results, they are consistent with Morrison (2014). This

finding is unexpected given the body of evidence that links obsessive-

compulsiveness and inferential confusion. However, until now, most studies

have used either the self-report ICQ or ICQ-EV (Aardema et al., 2005;

Aardema et al., 2008, Aardema et al., 2006; Aardema et al., 2010). It could be

argued that the ICQ-EV might correlate with the self-report measures in this

study because inferential confusion is merely another re-expression of the

issues measured by the OCI-R, MIS and DES-II. Like them, the ICQ-EV is

also a self -report tool and so a subjective measure of participants’ experience.

Despite the strong relationship found between experimentally-induced

inferential confusion and dissociation in the delusions-relevant scenario of the

IPT, similarly to Morrison’s (2014) findings, no significant relationship was

found between dissociation and experimentally-induced inferential confusion

in either of the original OC-relevant or neutral scenarios. This finding could be

taken to support the notion that dissociation is involved in inferential

confusion, but only when inferential confusion is occurring in a realm that

relates to delusions and/or schizotypy. In addition, it could be used to support

O’Connor and Aardema’s (2012) idea that dissociation may be what enables

absorption into the imaginary for people experiencing inferential confusion.

However, that this outcome was only evident in the delusion-relevant scenario

of the IPT allows for an alternative explanation to be made regarding the

hypotheses that were not supported. Dissociation was strongly correlated with

40

the measures of both schizotypy and obsessive-compulsiveness, which is

consistent with previous literature that has linked dissociation and obsessive-

compulsiveness (Aardema & Wu, 2011) and dissociation and schizotypy

(Merckelbach Rassin & Muris, 2000). Inferential confusion as measured by

the ICQ-EV also correlated with all measures as expected, whereas the IPT

did not. Therefore, rather than the findings of the current study going against

what is in the literature with regards to the relationship between inferential

confusion and obsessive-compulsiveness, it might be postulated that the IPT

does not operationalize inferential confusion in the manor by which it claims

to.

The main limitation of the current study is that the delusion-relevant

scenario of the IPT is yet to be replicated. This was the only condition of the

experimental task that yielded positive results. However, these single findings

cannot be considered reliable or valid until replication is undertaken. The

delusion-relevant scenario could have been designed to represent a more

common delusional experience, rather than that of being car-jacked. For

example, the experience of walking home at night alone and suspecting one

may be being followed. In retrospect, the possibility-based information in the

delusion-relevant scenario may have been different to that of the other two

scenarios. P2, P3 and P4 appear to be based on ‘reality’ as opposed to

‘possibility’, when compared to the Ps in the other two scenarios, which are

more based on ‘maybe’. For example, P2 in the delusion-relevant scenario

uses definite language such as “Other cars have overtaken you and the car

behind at other points in your journey” whereas P2 in the OC-relevant uses

more ambiguous language, “You may not have seen everything, because it’s

41

quite crowded.” In hindsight, the possibility-based pieces of information at

time points P2, P3 and P4 in the delusion- relevant scenario were in fact more

like the reality-based pieces of information in the other two scenarios. Based

on the results of the other two scenarios, P2 of the delusion-relevant scenario

being more like a reality-based piece of information. This may explain why P2

reduced doubt in this scenario rather than increased it, as P2 did in the other

two scenarios. However, P3 and P4 of the delusion-relevant scenario increased

doubt even though they were more reality-based than the P’s in the other two

scenarios. An explanation for this could be that P3 and P4 of the delusion-

relevant scenario may have re-triggered the initial threat induced by the

scenario itself, as opposed to the possibility of what might have happened in

the scenario. If so, a possible conclusion could be that threat is a core

component of inferential confusion, as opposed to doubt, since this was the

scenario that related to the other measures of the study, including the self-

report measure of inferential confusion. “Possibly, the impact of reality-based

information is more attenuated in ego-syntonic obsessions, or obsessions that

resemble overvalued ideas or delusions.” (Aardema et al., 2009, p. 202). In

addition, it is unlikely that the impact of P3 and P4 in the delusion-relevant

scenario was due to the practice effects of the other scenarios, as the order that

the scenarios were presented in was randomised.

A further limitation is while the positive relationships found were strong

and in the expected direction, due to the correlational design of the study,

causation cannot be inferred. This does not allow conclusions as to whether

obsessive-compulsiveness, schizotypy or dissociative tendencies influence

inferential confusion or vice versa. Due to these reasons, the findings do not

42

aid the understanding of the causal sequence in inferential confusion but rather

what phenomena relate to the inferential confusion reasoning style. Direct

comparison with the findings of Aardema et al. (2009) and Morrison (2014)

are hampered somewhat by the studies using different measures of obsessive-

compulsiveness and inferential confusion. However, Morrison did use the

DES-II and the experimental IPT and the findings of the current study are

broadly consistent with Morrison’s (2014).

While Aardema and Wu (2011) found the absorption subscale of the

DES-II to correlate with inferential confusion, Morrison (2014) reported that

other aspects of dissociation had been linked with obsessive-compulsiveness

in the literature. For this reason, and for the purposes of comparison with the

results of Morrison’s (2014) study, the DES-II was used as a broad measure of

dissociation in the current study. This allowed for the investigation of the

relationship between inferential confusion, obsessive-compulsiveness,

schizotypy and dissociation, despite the lack of clarity around what aspects or

subtypes of dissociation may be most relevant to the other variables. Magical

Ideation was measured by the MIS as a symptom of schizotypy. This scale

was used since magical ideation is a phenomena that has also been linked to

some aspects of obsessive-compulsiveness (Tolin, Abramowitz, Kozac and

Foa, 2001). Therefore it was considered to be a relevant measure given the

variables that were investigated in the current study. However, the limitations

of this measure imply that schizotypy, as discussed in this paper, may not

completely represent the phenomena of schizotypy that the study was claiming

to investigate. The use of this measure may have inflated the observed

relationship between schizotypy and obsessive-compulsiveness, due to the

43

previously identified relationship between obsessive-compulsives and magical

ideation. Alternative measures of schizotypy such as the Oxford-Liverpool

Inventory of Feelings & Experiences (O-LIFE, Mason, Claridge & Jackson,

1995) may have been more representative of the phenomena in its entirety. In

turn, this may have enhanced the validity of the relationships found between

schizotypy and the other variables measured.

In both the current study and Morrison’s (2014) study, a non-clinical

sample was used, which while appropriate in this kind of research, does not

represent the clinical population to whom the findings from this type of

research may impact. The completion rate of the study was low, however the

demographics of those who dropped out were not included in the study. This

was in order to respect participants’ right to withdraw at any time, but it also

means that an understanding of the high drop out rate cannot be acquired.

The results support the idea that dissociation plays a role in inferential

confusion, obsessive-compulsiveness and schizotypy, as predicted by

Morrison (2014) and in line with the previous findings of Aardema and Wu

(2011) and O’Connor & Aardema (2012). The null results question Aardema

et al.’s (2009) claims that possibility-based information induces a doubting

process that emulates inferential confusion in people who experience high

levels of obsessive-compulsiveness, in OC-relevant threat situations. Since

Aardema et al. (2009) are the only research team to have found this effect,

which has not been found in two subsequent replications, it cannot currently

be supported and alternative explanations should be investigated.

Future research could focus on continuing to develop an experimentally

valid method to operationalize inferential confusion. Since this reasoning style

44

has been implicated in different phenomena that involve unusual thinking, the

IPT could be further extended to reflect this. Given the possibility-based

information in the delusion-relevant scenario later appeared to be more reality-

based than intended, adaptation of the IPT to encapsulate this could be useful

in deciphering what it was about the impact of information in the delusion-

relevant scenario that correlated with the ICQ-EV. For example, cumulative

impact of pairs of reality-based information concerning a inferred event

having occurred and not occurred could be compared to cumulative impact of

pairs of possibility-based information for the same scenario using a between

subjects design. This may help to identify what type of information is more

likely to induce inferential confusion, which would add to the accurate

explanation of why this reasoning process occurs.

To allow for causation to be implied, future studies may benefit from

including an experimental condition that induces the other variables of

interest, if ethically sound. For example, inducing and measuring feelings of

dissociation in participants before and after the IPT, to evaluate whether

dissociation increases an individual’s propensity to inferential confusion or

vice versa. Studies utilising a clinical sample to participate in expanded and

adapted versions of the IPT would also be useful. These would investigate

whether the same patterns are seen in clinical populations, which would in

turn enable findings to be generalised and utilized in a way that might inform

treatment for those significantly distressed by inferential confusion and the

phenomena related to it, i.e. obsessive-compulsiveness, schizotypy and

dissociation.

45

The finding that inferential confusion as measured by the ICQ-EV is

significantly related to obsessive-compulsiveness, schizotypy and dissociation

might have implications for the use of the IBA in treating delusional disorders

and dissociative disorders as well as OCD and related disorders. To further

quantify the trandiagnostic properties of the inferential confusion theory,

research has been conducted into other obsessive-compulsive spectrum

disorders, where beliefs are more akin to delusions or overvalued ideas, given

that they are ego-syntonic. Body-dysmorphic disorder and hoarding have both

been shown to be positively responsive to the IBA to treatment, suggesting

that inferential confusion theory could explain the unusual reasoning also seen

in these disorders (Tallion, O’Connor, Dupuis & Lavoie, 2013; St-Pierre-

Delorme, Lalonde, Perreault, Koszegi & O’Connor, 2011), supporting the

inferential confusion theory’s position as a possible transdiagnostic model for

disorders on the continuum of obsessive-compulsiveness, OVI and delusions.

In addition, findings from this study highlight the potential conceptual

similarities between self-report inferential confusion, obsessive-

compulsiveness schizotypy and dissociation. That is, inferential confusion

might merely be a re-expression of obsessive-compulsiveness, schizotypal and

dissociative phenomenology. To investigate this further, future research could

examine the relationship between the ICQ-EV and experimentally induced

inferential confusion using the IPT, while controlling for levels of obsessive-

compulsiveness, schizotypy and dissociation. This line of inquiry could help to

either validate inferential confusion as a state and trait construct separate to

similar phenomenology, or further question its construct and clinical reliability

and validity.

46

Conclusion

This study demonstrates that inferential confusion, obsessive-

compulsiveness, schizotypy and dissociation are linked. However, it does not

determine the causation of these relationships. In highlighting the need for

further investigation of the mechanisms by which inferential confusion occurs,

the current study offers threat activation as an alternative explanation of

inferential confusion to the doubting process that is put forward by the original

inferential confusion theory (O’Connor et al., 2005). This study questions the

validity of the Inference Process Task claimed by Aardema et al (2009) to

measure inferential confusion and provides a novel level to the task to widen

the remit of what it investigates. The present study suggests adaptations to be

made to the IPT to investigate alternative avenues that may represent

inferential confusion more accurately and proposes methodological

adaptations that future studies could make to enhance the reliability and

validity of possible findings. Future research in this area is shown to be both

justifiable and desirable. The need to decipher whether inferential confusion is

an independent construct or merely a re-expression of obsessive-

compulsiveness, schizotypy and dissociation still remains, as does the need for

the replication of a valid experimental measure of inferential confusion. Future

research that can demonstrate the direction of the relationships found by the

current study could enhance the use of the inference based approach to therapy

for adults and children experiencing a wide range of obsessive-compulsive and

related phenomena, as well as those experiencing other thought disorders,

including but not limited to schizotypy and dissociation.

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References

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Inferential confusion, cognitive change and treatment outcome in obsessive-

compulsive disorder. Clinical Psychology & Psychotherapy,12, 338-345.

Aardema, F., O'Connor, K. P., & Emmelkamp, P. M. G. (2006).

Inferential confusion and obsessive beliefs in obsessive-compulsive

disorder. Cognitive Behaviour Therapy, 35, 138-147. 

Aardema, F., O'Connor, K. P., Emmelkamp, P. M. G., Marchand, A.,

& Todorov, C. (2005). Inferential confusion in obsessive-compulsive disorder:

The inferential confusion questionnaire. Behaviour Research and Therapy, 43,

293-308.

Aardema, F., & O'Connor, K. (2012). Dissolving the tenacity of

obsessional doubt: Implications for treatment outcome. Journal of Behavior

Therapy and Experimental Psychiatry, 43, 855-861.

Aardema, F., O'Connor, K. P., Pélissier, M., & Lavoie, M. E. (2009).

The quantification of doubt in obsessive-compulsive disorder. International

Journal of Cognitive Therapy, 2, 188-205. 

Aardema, F., Radomsky, A. S., O'Connor, K. P., & Julien, D. (2008).

Inferential confusion, obsessive beliefs and obsessive-compulsive symptoms:

A multidimensional investigation of cognitive domains. Clinical Psychology

& Psychotherapy, 15, 227-238.

Aardema, F., & Wu, K. D. (2011). Imaginative, dissociative, and

schizotypal processes in obsessive-compulsive symptoms. Journal of Clinical

Psychology, 67, 74-81. 

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Aardema, F., Wu, K.D., Careau, Y., O’Connor, K., Julien, D., &

Dennie, S. (2010). The Expanded Version of the Inferential Confusion

Questionnaire: Further Development and Validation in Clinical and Non-

Clinical Samples. J Psychopathol Behav Assess, 32, 448-462.

American Psychiatric Association (2014). Diagnostic and statistical

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Abramowitz, J. S., Taylor, S., & McKay, D. (2009). Obsessive-

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Bell, V., Halligan, P. W., & Ellis, H. D. (2006). Explaining delusions:

a cognitive perspective. Trends in cognitive sciences, 10(5), 219-226.

Ethics Committee of the British Psychological Society (2009). Code of

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Carlson, E. B., & Putnam, F. W. (1993). An update on the dissociative

experiences scale. Dissociation: Progress in the Dissociative Disorders, 6(1),

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Claridge, G., McCreery, C., Mason, O., Bentall, R., Boyle, G., Slade,

P., & Popplewell, D. (1996). The factor structure of ‘schizotypal’ traits: A

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UK Parliament (1998). Data Protection Act. London: HMSO.

Eckblad, M., & Chapman, L. J. (1983). Magical ideation as an

indicator of schizotypy. Journal of consulting and clinical psychology, 51(2),

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Foa, E. B., Huppert, J. D., Leiberg, S., Langner, R., Kichic, R., Hajcak,

G., & Salkovskis, P. M. (2002). The Obsessive-Compulsive Inventory:

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Gibbs, N.A. (1996). Nonclinical populations in research on obsessive

compulsive disorder: A critical review. Clinical Psychology Review, 16, 729-

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Johns, L.C., & Os, J.V. (2001). The continuity of psychotic

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Mason, O., Claridge, G., & Jackson, M. (1995). New scales for the

assessment of schizotypy. Personality and Individual differences, 18(1), 7-13.

Morrison, K. (2014). The Relationship Between Dissociation,

Susceptibility to Doubt and Obsessive- Compulsiveness. Unpublished

Manuscript.

Merckelbach, H., Rassin, E., & Muris, P. (2000). Dissociation,

schizotypy, and fantasy proneness in undergraduate students. The Journal of

nervous and mental disease, 188(7), 428-431.

O'Connor, K., & Aardema, F. (2003). Fusion or confusion in

obsessive-compulsive disorder. Psychological Reports, 93, 227-232.

O'Connor, K., & Aardema, F. (2012). Living in a Bubble Dissociation,

Relational Consciousness, and Obsessive Compulsive Disorder. Journal of

Consciousness Studies, 19(7-8), 216-246.

Obsessive Compulsive Cognitions Working Group. (2005).

Psychometric validation of the obsessive belief questionnaire and

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interpretation of intrusions inventory—Part 2: Factor analyses and testing of a

brief version. Behaviour Research and Therapy, 43(11), 1527-1542.

O’Connor, K., Aardema, F., & Pelissier, M. (2005). BEYOND

REASONABLE DOUBT: Reasoning Processes in Obsessive-Compulsive

Disorder and Related Disorders. England: John Wiley & Sons, Ltd.

O'Connor, K., Koszegi, N., Aardema, F., van Niekerk, J., & Taillon, A.

(2009). An inference-based approach to treating obsessive-compulsive

disorders. Cognitive and Behavioral Practice, 16(4), 420-429.

O'Connor, K., & Robillard, S. (1995). Inference processes in

obsessive-compulsive disorder: Some clinical observations. Behaviour

Research and Therapy, 33, 887-896.

Tallion, A., O’Connor, K., Dupius, G., & Lavoie, M. (2013).

Inference-Based Therapy for Body Dysmorphic Disorder. Clinical Psychology

and Psychotherapy, 20, 67-76.

Tolin, D. F., Abramowitz, J. S., Kozak, M. J., & Foa, E. B. (2001).

Fixity of belief, perceptual aberration, and magical ideation in obsessive–

compulsive disorder. Journal of Anxiety Disorders, 15(6), 501-510.

St-Pierre-Delorme, M., Lalonde, M.P., Perreault, V., Koszegi, N., &

O’Connor, K. (2001). Inference-Based Therapy for Compulsive Hoarding: A

Clinical Case Study. Clinical Case Studies, 10, 291-303.

Van Ijzendoorn, M. H., & Schuengel, C. (1996). The measurement of

dissociation in normal and clinical populations: Meta-analytic validation of the

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365-382.

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Major Research Project – List of Appendices

Appendix A – Journal Guidelines for authors

Appendix B – IPT

Appendix C – ICQ-EV, DES, OCI, MI

Appendix D – Information/consent/debrief/advertising material

Appendix E - Demographic questions

Appendix F – Ethics committee letter

Appendix G – Tables of demographics

Appendix H – Normality plots/histograms

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Appendix A – Journal Guidelines for authors

Retrieved from http://www.elsevier.com/journals/journal-of-obsessive-compulsive-and-related-disorders/2211-3649?generatepdf=true

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Authors must identify who provided financial support for the conduct of the research and/or preparation of the manuscript and to briefly describe the role (if any) of the funding sponsor in study design, collection, analysis, or interpretation of data, writing the manuscript, and the decision to submit the manuscript for publication. If the funding source had no such involvement, the authors should so state.

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Authors must declare their individual contributions to the manuscript. All authors must have materially participated in the research and/or the manuscript preparation. Roles for each author should be described. The disclosure must also clearly state and verify that all authors have approved the final manuscript.

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Article structure

Introduction

State the objectives of the work and provide an adequate background, avoiding a detailed literature survey or a summary of the results. If the focus of the paper is on a disorder other than OCD (as defined in DSM-IV.TR), provide a rationale for including the disorder as an obsessive-compulsive related disorder (see Editorial Guidance section).

Methods

Provide sufficient detail to allow the work to be reproduced. Methods already published should be indicated by a reference: only relevant modifications should be described.

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A Theory section should extend, not repeat, the background to the article already dealt with in the Introduction and lay the foundation for further work. In contrast, a Calculation section represents a practical development from a theoretical basis.

Results

Results should be clear and concise.

Discussion

This should explore the significance of the results of the work, not repeat them. Avoid extensive citations and discussion of published literature. Be sure to include limitations of the present study and suggestions for future research.

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The main conclusions of the study may be presented in a short Conclusions section, which may stand alone or form a subsection of a Discussion or Results and Discussion section.

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Clinical reports and case histories

The Journal will consider clinical reports that articulate the treatment of OCD or related disorders using any theoretical framework (biological, behavioral, cognitive, gestalt, humanistic, psychodynamic, and others). Clinical reports should use the following format (maximum manuscript length is 30 pages in total):

1. Theoretical and Research Basis for the Treatment2. Case Introduction (presenting complaints, history, etc.)3. Assessment (what instruments were used [and justification if needed])4. Case Conceptualization (discuss the clinician's thinking about the case and the treatment selection) 5. Course of Treatment and Assessment of Progress (Describe what happened during treatment and the outcome at post-treatment and follow up. If possible, use single case research design methodology; see Barlow, Nock, &Hersen [2009])

6. Complicating Factors (if any, including medical management) 7. Treatment Implications of the Case8. Recommendations to Clinicians and Students

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This option is designed to allow publication of research reports that are not suitable for publication as regular articles. Shorter Communications or Brief Reports are appropriate for articles with a specialized focus or of particular didactic value. Manuscripts should be between 3000-5000 words, and must not exceed the upper word limit. This limit includes the abstract, text, and references, but not the title page, tables and figures.

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A concise and factual abstract is required. The abstract should state briefly the purpose of the research, the principal results and major conclusions. An abstract is often presented separately from the article, so it must be able to stand alone. For this reason, References should be avoided, but if essential, then cite the author(s) and year(s). Also, non-standard or uncommon abbreviations should be avoided, but if essential they must be defined at their first mention in the abstract itself.

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Highlights

Highlights are mandatory for this journal. They consist of a short collection of bullet points that convey the core findings of the article and should be submitted in a separate editable file in the online submission system. Please use 'Highlights' in the file name and include 3 to 5 bullet points (maximum 85 characters, including spaces, per bullet point). See http://www.elsevier.com/highlights for examples.

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Keywords

Immediately after the abstract, provide a maximum of 6 keywords, using American spelling and avoiding general and plural terms and multiple concepts (avoid, for example, 'and', 'of'). Be sparing with abbreviations: only abbreviations firmly established in the field may be eligible. These keywords will be used for indexing purposes.

Acknowledgements

Collate acknowledgements in a separate section at the end of the article before the references and do not, therefore, include them on the title page, as a footnote to the title or otherwise. List here those individuals who provided help during the research (e.g., providing language help, writing assistance or proof reading the article, etc.).

Math formulae

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Footnotes

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Artwork

Electronic artwork General points

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• Make sure you use uniform lettering and sizing of your original artwork.• Preferred fonts: Arial (or Helvetica), Times New Roman (or Times), Symbol, Courier.• Number the illustrations according to their sequence in the text.• Use a logical naming convention for your artwork files.• Indicate per figure if it is a single, 1.5 or 2-column fitting image.• For Word submissions only, you may still provide figures and their captions, and tables within a single file at the revision stage.• Please note that individual figure files larger than 10 MB must be provided

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in separate source files. A detailed guide on electronic artwork is available on our website: http://www.elsevier.com/artworkinstructions.You are urged to visit this site; some excerpts from the detailed information are given here. FormatsRegardless of the application used, when your electronic artwork is finalized, please 'save as' or convert the images to one of the following formats (note the resolution requirements for line drawings, halftones, and line/halftone combinations given below):EPS (or PDF): Vector drawings. Embed the font or save the text as 'graphics'.TIFF (or JPG): Color or grayscale photographs (halftones): always use a minimum of 300 dpi.TIFF (or JPG): Bitmapped line drawings: use a minimum of 1000 dpi.TIFF (or JPG): Combinations bitmapped line/half-tone (color or grayscale): a minimum of 500 dpi is required.Please do not:• Supply files that are optimized for screen use (e.g., GIF, BMP, PICT, WPG); the resolution is too low. • Supply files that are too low in resolution.• Submit graphics that are disproportionately large for the content.

Color artwork

Please make sure that artwork files are in an acceptable format (TIFF (or JPEG), EPS (or PDF), or MS Office files) and with the correct resolution. If, together with your accepted article, you submit usable color figures then Elsevier will ensure, at no additional charge, that these figures will appear in color online (e.g., ScienceDirect and other sites) regardless of whether or not these illustrations are reproduced in color in the printed version. For color reproduction in print, you will receive information regarding the costs from Elsevier after receipt of your accepted article. Please indicate your preference for color: in print or online only. For further information on the preparation of electronic artwork, please see http://www.elsevier.com/artworkinstructions.

Please note: Because of technical complications that can arise by converting color figures to 'gray scale' (for the printed version should you not opt for color in print) please submit in addition usable black and white versions of all the color illustrations.

Figure captions

Ensure that each illustration has a caption. A caption should comprise a brief title (not on the figure itself) and a description of the illustration. Keep text in the illustrations themselves to a minimum but explain all symbols and abbreviations used.

Tables

Please submit tables as editable text and not as images. Tables can be placed either next to the relevant text in the article, or on separate page(s) at the end.

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Number tables consecutively in accordance with their appearance in the text and place any table notes below the table body. Be sparing in the use of tables and ensure that the data presented in them do not duplicate results described elsewhere in the article. Please avoid using vertical rules.

References

Citation in text

Please ensure that every reference cited in the text is also present in the reference list (and vice versa). Any references cited in the abstract must be given in full. Unpublished results and personal communications are not recommended in the reference list, but may be mentioned in the text. If these references are included in the reference list they should follow the standard reference style of the journal and should include a substitution of the publication date with either 'Unpublished results' or 'Personal communication'. Citation of a reference as 'in press' implies that the item has been accepted for publication.

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Web references

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References in a special issue

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Reference management software

Most Elsevier journals have a standard template available in key reference management packages. This covers packages using the Citation Style Language, such as Mendeley (http://www.mendeley.com/features/reference-manager) and also others like EndNote (http://www.endnote.com/support/enstyles.asp) and Reference Manager (http://refman.com/support/rmstyles.asp). Using plug-ins to word processing packages which are available from the above sites, authors only need to select the appropriate journal template when preparing their article and the list of references and citations to these will be formatted according to the journal style as described in this Guide. The process of including templates in these packages is constantly ongoing. If the journal you are looking for does not have a template available yet, please see the list of sample references and

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citations provided in this Guide to help you format these according to the journal style.

If you manage your research with Mendeley Desktop, you can easily install the reference style for this journal by clicking the link below: http://open.mendeley.com/use-citation-style/journal-of-obsessive-compulsive-and-related-disorders When preparing your manuscript, you will then be able to select this style using the Mendeley plug- ins for Microsoft Word or LibreOffice. For more information about the Citation Style Language, visit http://citationstyles.org.

Reference formatting

There are no strict requirements on reference formatting at submission. References can be in any style or format as long as the style is consistent. Where applicable, author(s) name(s), journal title/book title, chapter title/article title, year of publication, volume number/book chapter and the pagination must be present. Use of DOI is highly encouraged. The reference style used by the journal will be applied to the accepted article by Elsevier at the proof stage. Note that missing data will be highlighted at proof stage for the author to correct. If you do wish to format the references yourself they should be arranged according to the following examples:

Reference styleText: Citations in the text should follow the referencing style used by the American Psychological Association. You are referred to the Publication Manual of the American Psychological Association, Sixth Edition, ISBN 978-1-4338-0561-5, copies of which may be ordered from http://books.apa.org/books.cfm?id=4200067 or APA Order Dept., P.O.B. 2710, Hyattsville, MD 20784, USA or APA, 3 Henrietta Street, London, WC3E 8LU, UK.List: references should be arranged first alphabetically and then further sorted chronologically if necessary. More than one reference from the same author(s) in the same year must be identified by the letters 'a', 'b', 'c', etc., placed after the year of publication.Examples:Reference to a journal publication:Van der Geer, J., Hanraads, J. A. J., & Lupton, R. A. (2010). The art of writing a scientific article. Journal of Scientific Communications, 163, 51–59.Reference to a book:Strunk, W., Jr., & White, E. B. (2000). The elements of style. (4th ed.). New York: Longman, (Chapter 4).Reference to a chapter in an edited book:Mettam, G. R., & Adams, L. B. (2009). How to prepare an electronic version of your article. In B. S. Jones, & R. Z. Smith (Eds.), Introduction to the electronic age (pp. 281–304). New York: E-Publishing Inc.

Journal abbreviations source

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Journal names should be abbreviated according to the List of Title Word Abbreviations: http://www.issn.org/services/online-services/access-to-the-ltwa/.

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Video data

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AudioSlides

The journal encourages authors to create an AudioSlides presentation with their published article. AudioSlides are brief, webinar-style presentations that are shown next to the online article on ScienceDirect. This gives authors the opportunity to summarize their research in their own words and to help readers understand what the paper is about. More information and examples are available at http://www.elsevier.com/audioslides. Authors of this journal will automatically receive an invitation e-mail to create an AudioSlides presentation after acceptance of their paper.

Supplementary material

Elsevier accepts electronic supplementary material to support and enhance your scientific research. Supplementary files offer the author additional possibilities to publish supporting applications, high- resolution images, background datasets, sound clips and more. Supplementary files supplied will be published online alongside the electronic version of your article in Elsevier Web products, including ScienceDirect: http://www.sciencedirect.com. In

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order to ensure that your submitted material is directly usable, please provide the data in one of our recommended file formats. Authors should submit the material in electronic format together with the article and supply a concise and descriptive caption for each file. For more detailed instructions please visit our artwork instruction pages at http://www.elsevier.com/artworkinstructions.

3D neuroimaging

You can enrich your online articles by providing 3D neuroimaging data in NIfTI format. This will be visualized for readers using the interactive viewer embedded within your article, and will enable them to: browse through available neuroimaging datasets; zoom, rotate and pan the 3D brain reconstruction; cut through the volume; change opacity and color mapping; switch between 3D and 2D projected views; and download the data. The viewer supports both single (.nii) and dual (.hdr and .img) NIfTI file formats. Recommended size of a single uncompressed dataset is maximum 150 MB. Multiple datasets can be submitted. Each dataset will have to be zipped and uploaded to the online submission system via the '3D neuroimaging data' submission category. Please provide a short informative description for each dataset by filling in the 'Description' field when uploading a dataset. Note: all datasets will be available for downloading from the online article on ScienceDirect. If you have concerns about your data being downloadable, please provide a video instead. For more information see: http://www.elsevier.com/3DNeuroimaging.

Submission checklist

The following list will be useful during the final checking of an article prior to sending it to the journal for review. Please consult this Guide for Authors for further details of any item.Ensure that the following items are present:One author has been designated as the corresponding author with contact details:

• E-mail address• Full postal addressAll necessary files have been uploaded, and contain: • Keywords• All figure captions• All tables (including title, description, footnotes) Further considerations

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• Manuscript has been 'spell-checked' and 'grammar-checked'• All references mentioned in the Reference list are cited in the text, and vice versa• Permission has been obtained for use of copyrighted material from other sources (including the Internet)

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Printed version of figures (if applicable) in color or black-and-white• Indicate clearly whether or not color or black-and-white in print is required.• For reproduction in black-and-white, please supply black-and-white versions of the figures for printing purposes.For any further information please visit our customer support site at http://support.elsevier.com.

AFTER ACCEPTANCE

Use of the Digital Object Identifier

The Digital Object Identifier (DOI) may be used to cite and link to electronic documents. The DOI consists of a unique alpha-numeric character string which is assigned to a document by the publisher upon the initial electronic publication. The assigned DOI never changes. Therefore, it is an ideal medium for citing a document, particularly 'Articles in press' because they have not yet received their full bibliographic information. Example of a correctly given DOI (in URL format; here an article in the journal Physics Letters B):

http://dx.doi.org/10.1016/j.physletb.2010.09.059

When you use a DOI to create links to documents on the web, the DOIs are guaranteed never to change.

Online proof correction

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If preferred, you can still choose to annotate and upload your edits on the PDF version. All instructions for proofing will be given in the e-mail we send to authors, including alternative methods to the online version and PDF.We will do everything possible to get your article published quickly and accurately. Please use this proof only for checking the typesetting, editing, completeness and correctness of the text, tables and figures. Significant changes to the article as accepted for publication will only be considered at this stage with permission from the Editor. It is important to ensure that all corrections are sent back to us in one communication. Please check carefully before replying, as inclusion of any subsequent corrections cannot be guaranteed. Proofreading is solely your responsibility.

Offprints

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The corresponding author, at no cost, will be provided with a personalized link providing 50 days free access to the final published version of the article on ScienceDirect. This link can also be used for sharing via email and social networks. For an extra charge, paper offprints can be ordered via the offprint order form which is sent once the article is accepted for publication. Both corresponding and co-authors may order offprints at any time via Elsevier's WebShop (http://webshop.elsevier.com/myarticleservices/offprints). Authors requiring printed copies of multiple articles may use Elsevier WebShop's 'Create Your Own Book' service to collate multiple articles within a single cover (http://webshop.elsevier.com/myarticleservices/booklets).

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Appendix B – Inference Process Task (IPT)

You will read three scenarios. Take the time to use your imagination to visualise yourself in each scenario. After each scenario, you will be asked to rate your anxiety as if you were truly involved in the situation. You will also be asked to rate what you think the probability is that a possible event had occurred in each scenario. You will be presented with 8 statements about each scenario and asked to consider your rating of the probability of each possible event having occurred, in the light of each of these statements.

Scenario 1: You’re on your way to work with the car. This morning you read about an accident where a van driver unknowingly drove over someone, and left the scene of the accident without realising. You wonder how it is possible that someone could not notice this while driving. As you drive along, you come across an intersection and come to a halt at the red light. It is quite busy, with a lot of people on the other side of the intersection, waiting to cross the road. You notice a group of young people, boys and girls, chasing each other, running off and on the road. As the light turns green you start to accelerate. Then, just as you pass the intersection you hear a scream and feel a bump!

How anxious would you feel in the above situation?

Please rate this on a scale 0-100%……………………………………………..

What do you consider to be the probability that an accident has happened under these circumstances?

Please rate this on a scale 10-100%……………………………………………

R1. You look in the rear view mirror and see a pothole in the road.

What do you consider to be the probability that an accident has happened under these circumstances?

Please rate this on a scale 10-100%……………………………………………

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P1. The pothole may not have been deep enough to cause the bump.

What do you consider to be the probability that an accident has happened under these circumstances?

Please rate this on a scale 10-100%……………………………………………

R2. Your turn your head and see no one lying on the street.

What do you consider to be the probability that an accident has happened under these circumstances?

Please rate this on a scale 10-100%……………………………………………

P2. You may not have seen anything because it is quite crowded.

What do you consider to be the probability that an accident has happened under these circumstances?

Please rate this on a scale 10-100%……………………………………………

R3. You watch the expressions on people’s faces and see no emotion that may indicate an accident.

What do you consider to be the probability that an accident has happened under these circumstances?

Please rate this on a scale 10-100%…………………………………………….

P3. The lack of expression in people’s faces may have been shock.

What do you consider to be the probability that an accident has happened under these circumstances?

Please rate this on a scale 10-100%……………………………………………

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R4. The car behind you did not stop as you would expect had there been an accident.

What do you consider to be the probability that an accident has happened under these circumstances?

Please rate this on a scale 10-100%…………………………………………….

P4. Perhaps the driver of the car behind you did not see what had happened either because it was so busy.

What do you consider to be the probability that an accident has happened under these circumstances?

Please rate this on a scale 10-100%……………………………………………

Scenario 2: You’re on your way to work with the car. This morning you read about the rise of carjacking’s in your local area. The article explained that carjacking is the forceful theft of an occupied vehicle that often involves the victim being robbed of other valuables, abducted and assaulted. The carjackers had been forcing their victims to stop the car by overtaking them and halting abruptly in front of them. You wonder how it is possible that the police have not yet caught the perpetrators. As you drive along, you come to an intersection and come to a halt at the red light. The roads are not that busy and you noticed that a car with an overseas licence plate has been driving behind you the whole journey. As the light turns green you start to accelerate. Then as you pass the intersection, the car behind drives to the side of you and the men inside the car stare into your car.

How anxious would you feel in the above situation?

Please rate this on a scale 0-100%……………………………………………

What do you consider to be the probability that the men in the car are going to car jack you?

Please rate this on a scale 10-100%……………………………………………

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R1. The expressions on the men’s faces in the car are not menacing or threatening in anyway.

What do you consider to be the probability that the men in the car are going to car jack you?

Please rate this on a scale 10-100%……………………………………………

P2. The lack of expression in their faces may be because they want to take you be surprise.

What do you consider to be the probability that the men in the car are going to car jack you?

Please rate this on a scale 10-100%……………………………………………

R2. It is not very busy and you are in a much safer place for the car to overtake you now than at other points in the journey.

What do you consider to be the probability that the men in the car are going to car jack you?

Please rate this on a scale 10-100%…………………………………………….

P2. Other cars have overtaken you and the car behind at other points in your journey.

What do you consider to be the probability that the men in the car are going to car jack you?

Please rate this on a scale 10-100%……………………………………………

R3. The number plate indicates that the drivers are from a country where they drive on the other side of the road.

What do you consider to be the probability that the men in the car are going to car jack you?

Please rate this on a scale 10-100%……………………………………………

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P3. The drivers have managed to stay on the correct side of the road for the whole journey up until this point.

What do you consider to be the probability that the men in the car are going to car jack you?

Please rate this on a scale 10-100%……………………………………………

R4. You realise that you are driving way below the speed limit.

What do you consider to be the probability that the men in the car are going to car jack you?

Please rate this on a scale 10-100%…………………………………………….

P4. You have been driving below the speed limit at other points in the journey and the car has not overtaken you.

What do you consider to be the probability that the men in the car are going to car jack you?

Please rate this on a scale 10-100%……………………………………………

Scenario 3: You are on your way to a restaurant for an evening out with your friends. You have decided to take the bus to save some money, even though the possibility of a bus strike was announced on the news yesterday. Once you arrive at the bus stop you wait for 20 minutes with several people standing beside you and still no bus has arrived. Then you overhear something about a ‘strike’. Soon afterwards most of the people around you disappear.

How anxious would you feel in the above situation?

Please rate this on a scale 0-100%……………………………………………..

What do you consider to be the probability that there was a bus strike under these circumstances?

Please rate this on a scale 10-100%……………………………………………

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R1. At the end of the street you see a bus driving on what appears to be a different route.

What do you consider to be the probability that there was a bus strike under these circumstances?

Please rate this on a scale 10-100%……………………………………………

P1. Maybe the bus was out of service since you could not see whether there were any people in it.

What do you consider to be the probability that there was a bus strike under these circumstances?

Please rate this on a scale 10-100%……………………………………………

R2. A person tells you he took the bus earlier in the day.

What do you consider to be the probability that there was a bus strike under these circumstances?

Please rate this on a scale 10-100%……………………………………………

P2. The strike may have only started later in the day.

What do you consider to be the probability that there was a bus strike under these circumstances?

Please rate this on a scale 10-100%……………………………………………

R3. You call the information service and get an automated message with no mention of any strike.

What do you consider to be the probability that there was a bus strike under these circumstances?

Please rate this on a scale 10-100%……………………………………………

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P3. Maybe the bus station doesn’t give out this type of information that quickly.

What do you consider to be the probability that there was a bus strike under these circumstances?

Please rate this on a scale 10-100%……………………………………………

R4. The bus you want to get has been late a lot recently due to there having been roads works on its route.

What do you consider to be the probability that there was a bus strike under these circumstances?

Please rate this on a scale 10-100%……………………………………………

P4. The road works were expected to have finished by now.

What do you consider to be the probability that there was a bus strike under these circumstances?

Please rate this on a scale 10-100%……………………………………………

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Appendix C – ICQ-EV, DES, OCI, MI

Inferential Confusion Questionnaire – Expanded Version Please rate your agreement or disagreement with the following statements using the scale

1 Strongly disagree2 Disagree3 Somewhat disagree 4 Somewhat agree 5 Agree6 Strongly agree

Answer 1-61. I am sometimes more convinced about what might be here than by what I actually see2. I sometimes invent stories about certain problems that night be here without paying attention to what I actually see3. Sometimes certain far fetched ideas feel so real they could just as well be happening4. Often my mind starts to race and I come up with all kinds of far fetched ideas5. I can get very easily absorbed in remote possibilities that feel as if they are real6. I often confuse different events as if they were the same7. I often connect ideas or events in my mind that would seem far fetched to others or even me8. Certain disturbing thoughts of mine sometimes cast a shadow on to everything around me9. I sometimes forget who or where I am when I get absorbed in to certain ideas or stories10. My imagination is sometimes so strong that I feel stuck and unable to see things differently11. I invent arbitrary rules, which I then feel I have to live by12. I often cannot tell if something is safe, because things are not what they appear to be13. Sometimes every far fetched possibility my mind comes up with feel real to me14. I sometimes get so absorbed in certain ideas that I am completely unable to see things differently even if I try15. In order to tell whether there is problem or not I tend to look more for that which is hidden than what I can actually see16. Even if I don’t have any actual proof of a certain problem, my imagination can convince me otherwise17. Just the thought that there could be a problem or something wrong is proof enough for me that there is

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18. I can get so caught up in certain ideas of mine that I totally forget about everything around me

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19. Often when I feel certain about something a small detail comes to mind that puts everything into doubt20. I sometimes come up with far fetched reasons why there is a problem or something wrong, which then suddenly starts to feel real to me21. I often cannot get rid of certain ideas because I keep coming up with possibilities that confirm my ideas22. My imagination can make me loose confidence in what I actually perceive23. A mere possibility often has as much impact on me as reality itself24. Even if I have all sorts of visible evidence against the existence for a certain problem, I sill feel it will occur25. Even the smallest possibility can make can make me loose confidence in what I know26. I can imagine something and end up living it27. I am more often concerned with something that I cannot see rather than something I can see28. I sometimes come up with bizarre possibilities that feel real to me29. I often react to a scenario that might happen as if it is actually happening30. I sometimes cannot tell whether all the possibilities that enter my mind are real or not

Dissociative Experiences Scale-II (DES-II)

Directions: This questionnaire consists of 28 questions about experiences that you may have in your daily life. We are interested in how often you have these experiences. It is important, however, that your answers show how often these experiences happen to you when you are not under the influence of alcohol or drugs. To answer the questions, please determine to what degree the experience described in the question applies to you, and insert a number from the example below to show what percentage of the time you have the experience.

For example:

0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%

(Never) (Always)

Some people……. Percentage of time that this happens to you. Please use 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% or 100%

1…have the experience of driving or riding in a car or bus or subway and suddenly realizing that they don’t remember what has happened during all or part of the trip.2... find that sometimes they are listening to someone talk and they suddenly realize that they did not hear part or all of what was said.3… have the experience of finding themselves in a place and have no idea how they got there.4… have the experience of finding themselves dressed in clothes that they don’t remember putting on.

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5… have the experience of finding new things among their belongings that they do not remember buying.6… sometimes find that they are approached by people that they do not know, who call them by another name or insist that they have met them before.7… sometimes have the experience of feeling as though they are standing next to themselves or watching themselves do something and they actually see themselves as if they were looking at another person.8… are told that they sometimes do not recognise friends or family members.9… find that they have no memory for some important event in their lives (for example a wedding or graduation.10… have the experience of being accused of lying when they do not think that they have lied.11… have the experience of looking in a mirror and not recognising themselves.12… have the experience of feeling that other people, objects, and the world around them are not real.13… have the experience of feeling that their body does not seem to belong to them.14… have the experience of sometimes remembering a past event so vividly that they feel as if they were reliving that event.15… have they experience of not being sure whether things that they remember happening really did happen or whether they just dreamt them.16… have the experience of being in a familiar place but finding it strange and unfamiliar.17… find that when they are watching television or a movie they become so absorbed in the story that they are unaware of other

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events happening around them.18… find that they become so involved in a fantasy or daydream that it feels as though it were really happening to them.19… find that they sometimes are able to ignore pain.20… find that they sometimes sit staring off into space, thinking of nothing, and are not aware of the passage of time.21… sometimes find that when they are alone they talk out loud to themselves.22…find that in one situation they may act so differently compared with another situation that they feel almost as if they were two different people.23… sometimes find that in certain situations they are able to do things with amazing ease and spontaneity that would usually be difficult for them (for example, sports, work, social situations, etc.).24… sometimes find that they cannot remember whether they have done something or have just thought about doing that thing (for example, not knowing whether they have just mailed a letter or have just thought about mailing it).25… find evidence that they have done things that they do not remember doing.26… sometimes find writings, drawings, or notes among their belongings that they must have done but cannot remember doing.27… sometimes find that they hear voices inside their head that tell them to do things or comment on things that they are doing.28… sometimes feel as if they are looking at the world through a fog, so that people and objects appear far away or unclear.

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OCI – R

The following statements refer to experiences that many people have in their everyday lives. Circle the number that best describes HOW MUCH that experience has DISTRESSED OR BOTHERED you during the PAST MONTH. The numbers refer to the following verbal labels: 0 = Not at all, 1 = A little, 2 = Moderately, 3 = A lot, 4 = Extremely.

1. I have saved up so many things that they get in the way 0 1 2 3 4

2. I check things more often than necessary 0 1 2 3 4

3. I get upset if objects are not arranged properly 0 1 2 3 4

4. I feel compelled to count while I am doing things 0 1 2 3 4

5. I find it difficult to touch an object when I know it has been touched by strangers or certain people 0 1 2 3 4

6. I find it difficult to control my own thoughts 0 1 2 3 4

7. I collect things I don’t need 0 1 2 3 4

8. I repeatedly check doors, windows, drawers etc 0 1 2 3 4

9. I get upset if others change the way I have arranged things 0 1 2 3 4

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10. I feel I have to repeat certain numbers 0 1 2 3 4

11. I sometimes have to wash or clean myself simply because I feel contaminated 0 1 2 3 4

12. I am upset by unpleasant thoughts that come into my mind against my will 0 1 2 3 4

13. I avoid throwing things away because I am afraid I might need them later 0 1 2 3 4

14. I repeatedly check gas and water taps and light switches after turning them off 0 1 2 3 4

15. I need things to be arranged in a particular way 0 1 2 3 4

16. I feel that there are good and bad numbers 0 1 2 3 4

17. I was my hands more often and for longer than necessary 0 1 2 3 4

18.I frequently get nasty thoughts and have difficulty in getting rid of them 0 1 2 3 4

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Magical Ideation Scale

1. Some people can make me aware of them just by thinking about me.

 True       False

2. I have had the momentary feeling that I might not be human.

 True       False

3. I have sometimes been fearful of stepping on sidewalk cracks.

 True       False

4. I think I could learn to read other’s minds if I wanted to.

 True       False

5. Horoscopes are right to often for it to be coincidence.  

 True       False

6. Things sometimes seem to be in different places when I get home, even though no one has been there.

 True       False

7. Numbers like 13 and 7 have no special powers.  

 True       False

8. I have occasionally had the silly feeling that a TV or radio broadcaster knew I was listening to him.

 True       False

9. I have worried that people on other planets may be influencing what happens on earth.

 True       False

10. The government refuses to tell us the truth about flying saucers.

 True       False

11. I have felt that there were messages for me in the way things were arranged, like in a store window.

 True       False

12. I have never doubted that my dreams are the products of my own mind.

 True       False

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13. Good luck charms don’t work.

 True       False

14. I have noticed sounds on my records that are not there at other times.

 True       False

15. The hand motions that strangers make seem to influence me at times.

 True       False

16. I almost never dream about things before they happen.

 True       False

17. I have had the momentary feeling that someone’s place has been taken by a look-alike.

 True       False

18. It is not possible to harm others merely by thinking bad thoughts about them.

 True       False

19. I have sometimes sensed and evil presence around me, although I could not see it.

 True       False

20. I sometimes have a feeling of gaining or losing energy when certain people look at me or touch me.

 True       False

21. I have sometimes had the passing thought that strangers are in love with me.

 True       False

22. I have never had the feeling that certain thoughts of mine really belonged to someone else.

 True       False

23. When introduced to strangers, I rarely wonder whether I have known them before.

 True       False

24. If reincarnation were true, it would explain some unusual experiences I have had.

 True       False

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25. People often behave so strangely that one wonders if they are part of an experiment.

 True       False

26. At certain times I perform certain little rituals to ward off negative influences.

 True       False

27. I have felt that I might cause something to happen just by thinking too much about it.

 True       False

28. I have wondered whether the spirits of the dead can influence the living.

 True       False

29. At times I have felt that a professor’s lecture was meant especially for me.

 True       False

30. I have sometimes felt that strangers were reading my mind.

 True       False

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Appendix D – Information/consent/debrief/advertising material

INFORMATION SHEETTitle of study: The relationship between beliefs, behaviours and reasoning.

Background to the study: The study will investigate a type of reasoning process and how it relates to the different ways people can think, feel and behave. What participation involves:

1. You will be presented with a fictional scenario and asked to imagine yourself in it.

2. You will then be asked to complete two ratings about the scenario. 3. You will then be presented with 8 additional pieces of information

about the scenario and asked to re-rate one of your original ratings about the scenario in the light of each new piece of information.

4. You will be required to repeat the same process in relation to a further two different scenarios that you will imagine yourself in.

5. You will complete 4 questionnaires about specific ways you might think, feel or behave.

6. You will be given some space to write any additional comments you have about the study.

7. You will be debriefed about the study.Your entire participation is expected to last approximately 30 minutes. You may experience mild psychological distress or discomfort from engaging in the tasks that require you to imagine fictional scenarios. Should this be the case, relevant sources of information and advice for you to use will presented in the debrief at the end of the study.Withdrawing from the study: You have a right to withdraw from the study at any time without having to give a reason. You can do this by closing the online programme that the study is provided on. Any partially completed data will not be included in the study. As participation is anonymous, once you have completed the study your data cannot be withdrawn. Data protection: Your participation will remain confidential. The data you supply will be annoymised and you will never be identifiable from any publications or presentations arising from this research. All data will be stored securely on a password protected computer programme and processed in accordance with the principles of the Data Protection Act (1998).

This study has received a favourable ethical opinion from the Ethics Committee of the Faculty of Arts and Human Sciences at the University of Surrey. Concerns about any aspect of this study should be referred to Nakita O’Leary, Principle Investigator, or Dr Laura Simonds, the Research Supervisor.

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Nakita O’Leary Dr Laura SimondsTrainee Clinical Psychologist Lecturer University of Surrey School of Psychology Email: n.o’leary@surrey.ac.uk University of SurreyTelephone: 01483689447 Email: l.simonds@surrey.ac.uk

Telephone: 01483 68 6936

CONSENT FORM

I the undersigned voluntarily agree to take part in this study on the relationship between beliefs, behaviours and reasoning.

I have read and understood the information provided. I have been advised about any discomfort and possible ill effects on my health and well-being which may result. I have been given the opportunity to ask questions about the study and have understood the advice and information given as a result.

I agree to comply and fully co-operate with any virtual instruction given to me during my participation with the online study.

I understand that all personal data relating to volunteers is held and processed in the strictest confidence, and in accordance with the Data Protection Act (1998). I agree that I will not seek to restrict the use of the results of the study on the understanding that my anonymity is preserved.

I understand the data I supply may be used in other studies or for teaching purposes.

I understand that I am free to withdraw from the study at any time without needing to justify my decision and without prejudice.

I confirm that I have read and understood the above and freely consent to participating in this study. I have been given adequate time to consider my participation and agree to comply with the instructions and restrictions of the study.

Click here if you consent to taking part in this study.

DEBRIEF

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This study is concerned with a reasoning process called inferential confusion and its relationship to obsessive compulsiveness and delusions. Inferential confusion happens when a person is more influenced by what might be possible than by what their senses are telling them is probable and likely. Previous studies have found inferential confusion to be related to obsessive and compulsive thoughts, feelings and behaviour and there has been some preliminary evidence to support a similar link between inferential confusion and the experience of delusions.

How was this tested?In this study, you were asked to complete questionnaires that measured your levels of inferential confusion, dissociation, magical ideation and obsessive compulsiveness. You were also asked to consider three scenarios and rate the probability that an inferred event had occurred in each. You were then presented with 8 additional pieces of reality and possibility based information for each of the three scenarios and asked to reconsider your probability rating in the light of each of these pieces of information. All participants completed the same questionnaires and the same tasks, the order in which the scenarios were presented were randomly alternated for each participant.

Hypotheses and main questions:We expect to find that those who are more influenced by the possibility based information of the inference task (i.e. those that significantly increase their rating regarding the probability of the inferred even having occurred in light of possibility based information as compared to their responses to the reality based information) will score higher on the measures of inferential confusion, dissociation, magical ideation and obsessive compulsiveness.

Why is this important to study?Understanding the reasoning processes behind experiences such as obsessive compulsiveness and delusions will contribute to the development of therapy that can be used to help people for whom these experiences become significantly distressing, i.e. those diagnosed with obsessive-compulsive disorder and delusional disorder. It also promotes the understanding of such phenomena as that of a variation of human experience. This helps to reduce the stigma that people with these diagnoses may experience.

How can I access further information?Everyone in the general population has some level of obsessive compulsiveness and delusional thinking so this is nothing unusual. None of the questionnaires in this study can be used to diagnose obsessive compulsive disorder or delusional disorder. If participating in this study has caused you to feel upset in any way, or you would like further information with any of the issues raised by this study, you can find information and advice via the following national charitiesRethink Mental Illness0300 5000 927 (Monday - Friday 10am - 2pm, not including bank holidays)

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www.rethink.org

OCD-UK0845 120 3778.support@ocduk.orgwww.ocduk.org

What if I want to know more?If you are interested in learning more about inferential confusion, you may want to consult the book: Beyond reasonable doubt: Reasoning Processes in Obsessive Compulsive Disorder and related disorders (2005) by Kieron O’Connor, Frederick Aardema and Marie-Claude Pelissier.

If you would like to receive a report of this research when it is completed (or a summary of the findings), please contact Nakita O’Leary at n.o’leary@surrey.ac.uk.

If you have concerns about your rights as a participant in this experiment, please contact Nakita O’Leary, Principle Investigator, or Dr Laura Simonds, the Research Supervisor.

Nakita O’Leary Dr Laura SimondsTrainee Clinical Psychologist Lecturer University of Surrey School of Psychology Email: n.o’leary@surrey.ac.uk University of Surrey

Email: l.simonds@surrey.ac.uk

Thank you again for your participation. Please refrain from discussing the full details of this study to other potential participants until the study is complete in October 2014. This is so the study can maintain its validity.

Text for Poster and Online advert

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The relationship between beliefs, behaviour and reasoning

I am a trainee clinical psychologist and as part of my doctorate I am conducting a research study investigating the relationship between beliefs, behaviours and reasoning. I require men and women above the age of 17 who have experience of driving a car to participate.

This study involves accessing electronic questionnaires and an online task via the link below. The entire study participation is expected to last 30 minutes.

The data collected in this study will be treated confidentially and all information will be handled in accordance with the Data Protection Act of 1998. Participation is anonymous. You may withdraw from participation during the study without having to give a reason. Once you have completed the study your data cannot be withdrawn.

The study has received a favourable ethical opinion from the University of Surrey Faculty of Arts and Human Sciences Ethics Committee. Further questions or concerns about any aspect of this study may be referred to the Principle Investigator:

Nakita O’LearyTrainee Clinical PsychologistUniversity of SurreyEmail: n.o’leary@surrey.ac.uk Telephone: 01483689447

or the research supervisor:

Dr. Laura Simonds LecturerSchool of PsychologyUniversity of SurreyEmail: l.simonds@surrey.ac.uk Telephone: 01483 68 6936

Appendix E - Demographic questions

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Please answer each question as best as it describes you.

1. What is your age?

2. What is your gender?

Male Female Other?

3. How would you describe your ethnicity?

WhiteEnglish / Welsh / Scottish / Northern Irish / BritishIrish Gypsy or Irish Traveller Any other White background, please describe

Mixed / Multiple ethnic groupsWhite and Black Caribbean White and Black African White and Asian Any other Mixed / Multiple ethnic background, please describe

Asian / Asian BritishIndian Pakistani Bangladeshi Chinese Any other Asian background, please describe

Black / African / Caribbean / Black BritishAfrican Caribbean Any other Black / African / Caribbean background, please describe

Other ethnic groupArab Any other ethnic group, please describe

4. What is the highest level of education you have completed?

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General certificate secondary education A-levels Trade/Technical/Vocational training Associate Degree Bachelor’s Degree Master’s Degree Professional Degree Doctorate degree

5. What is your marital status?

Single, never married Married or civil partnership Widowed Divorces Separated

6. What is your employment status?

Employed for wages Self-employed Out of work and looking for work Out of work but not currently looking for work A homemaker A student Military Retired Unable to work

7. What is your religion?

No religion Christian (C.O.E, Catholic, Protestant and all other Christian denominations)Buddhist Hindu Jewish Muslim Sikh Any other religion (please describe)

8. From which country are you currently completing this survey?

Appendix F – Ethics committee letter

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Faculty of Arts and Human SciencesEthics Committee

Chair’s Action

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Proposal Ref: 1022-PSY-14

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Name of Student/Trainee:

NAKITA O’LEARY

Title of Project: The relationship between beliefs, behaviours and reasoning

Supervisor: Dr Laura Simonds

Date of submission:

Date of confirmation email:

8th April 2014

5th June 2014

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The above Research Project has been submitted to the FAHS Ethics Committee and has received a favourable ethical opinion from the Faculty of Arts and Human Sciences Ethics Committee with conditions. The conditions stipulated after ethical review have now been addressed and the relevant amended documents submitted as evidence prior to commencement of your study. The final list of documents reviewed by the Committee is as follows:Protocol Cover sheet Summary of the projectDetailed protocol for the projectParticipant Information sheetConsent FormThis documentation should be retained by the student/trainee in case this project is audited by the Faculty Ethics Committee.

Signed: _________________Professor Bertram OpitzChair

Dated:

Please note: If there are any significant changes to your proposal which require further scrutiny, please contact the Faculty Ethics Committee before proceeding with your Project

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Appendix G - Tables of demographics

Demographic n %Gender Male 18 16.8%

Female 87 81.3%Other 3 1.9%

Ethnicity White British 47 43.9%White Irish 6 5.6%White Other 25 23.4%White and Black Caribbean 4 3.7%White and Black African 4 3.7%Mixed Other 4 3.7%Indian 3 2.8%Pakistani 1 0.9%Asian Other 2 1.9%Black or Black British Caribbean 2 1.9%Black or Black British African 3 2.8%Black or Black British Other 2 1.9%Chinese 1 0.9%Other 3 2.8%

Marital Status Single/never married 66 61.7%Married or in Civil Partnership 24 22.4%Widowed 1 0.9%Divorced 3 2.8%Separated 2 1.9%Other 11 10.3%

Employment Status Employed for wages 52 48.6%Self-employed 7 6.5%Out of work and looking for work 3 2.8%Homemakers 5 4.7%Students 32 29.9%Military 1 0.9%Retired 3 2.8%Unable to work 1 0.9%Other 2 1.9%

Education No formal qualifications 23 21.5%GCSE/O-Levels/NVQ/ 19 17.8%Trade/Technical/Vocational 4 3.7%Associates Degree 9 8.4%Bachelor’s Degree 31 29.0%Master’s Degree 13 12.1%Professional Degree 1 0.9%Doctoral Degree 7 6.5%

Religion No religion 47 43.9%Christian C.O.E, Catholic, Protestant 45 42.1%Buddhist 1 0.9%Hindu 2 1.9%Jewish 2 1.9%Muslim 1 0.9%Sikh 1 0.9%Other 8 7.5%

Country United Kingdom 54 50.47%United States of America 43 40.19%Canada 5 4.6%Australia 2 1.9%Argentina 1 0.9%India 1 0.9%Singapore 1 0.9%

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Appendix H – Normality plots/histograms

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Major Research Project Proposal Form

URN: 6242742

Project Title: An experimental induction of Inferential Confusion and its

relationship to Obsessive-Compulsiveness and Schizotypy.

Introduction

Obsessional doubt has long been considered a feature of obsessive-

compulsive disorder (OCD). OCD is characterised by the presence of

obsessions (persistent and recurrent thoughts, impulses or images that cause

distress) and/or compulsions (mental acts or behaviours that are aimed at

reducing distress) that are perceived by the individual as either distressing,

time consuming or disruptive to functioning (DSM IV, 2000). Obsessive-

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compulsiveness is also seen in non-clinical populations and thus an obsessive-

compulsive continuum has been proposed, with diagnosable OCD at the

extreme end of this continuum (Gibbs, 1996).

O’Connor, Aardema and Pelissier (2005) propose a novel theory of

OCD that conceptualises it as a belief disorder. According to this theory,

obsessions are constructed as primary inferences of doubt about a possible

state of affairs that are influenced by unusual reasoning styles. In this theory, a

mental intrusion is an inference of doubt about reality that leads the individual

to distrust their physical senses in preference of this imaginary possibility

(O’Connor & Rollibard, 1995). An example of this would be, thinking that

one has left the cooker on. Subsequent compulsions (e.g. checking that the

cooker is off) fail to overcome the primary doubt given that the individual is

attempting to use reality to modify the imaginary. Thus, the doubt is never

resolved, only reinforced, and the cycle continues (O’Connor & Aardema,

2003). Due to the confusion noted between reality-based and imaginary states

of affairs, this theory of obsessive-compulsiveness (OC) is coined Inferential

Confusion (IC) (O’Connor et al., 2005).

Delusions are defined as false beliefs despite evidence to the contrary

(DSM IV, 2000). Johns and Os (2001) reviewed research on the experience of

delusions in the non-clinical population, concluding that the experience of

delusions lies on a continuum. Unusual experiences such as delusions are part

of what is termed by Claridge et al. (1996) as schizotypy. Schizotypy is a way

of construing non-clinical delusional type beliefs that lie on a continuum with

the delusions that are referred to in clinically diagnosed disorders. If we

consider OC and delusions together, unusual ways of thinking about reality,

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that are not shared by others and that are causally implausible and which lie on

a continuum of severity, appear to characterise both OC and delusions. In the

case of the latter, the term schizotypy has been used to characterise non-

clinical delusional phenomena. Given the similarities between these concepts

of human experience, IC has been proposed to be a possible explanation of

delusions as well as OC (Aardema, O’Connor, Emmelkamp, Marchand &

Todorovc, 2005).

The current evidence suggests that IC is consistently found to correlate

positively and significantly with OC symptoms and that it emerges as an

independent predictor of OC symptoms when controlling for OC beliefs,

mood and anxiety. Degree of IC is significantly related to OC symptom

severity and it has been demonstrated to explain some of the relationship

between doubt and OC (Aardema et al., 2008; Wu et al., 2009; Aardema, et

al., 2006; Polman et al., 2011; Grenier et al., 2010; Aardema et al., 2009;

Aardema et al., 2010). There is some moderate support for differences in

inductive and probabilistic reasoning in OC (Pelissier & O’Connor, 2002;

Pelissier et al., 2009; Fear & Healey, 1997) and delusions and schizotypy

(John & Dodgson, 1994; Sellen et al., 2005; Conway et al., 2002; Tsakanikos,

2004). The Inferential Based Approach (IBA) to treating OC symptoms has

been supported (Aardema et al., 2005; Aardema et al., 2010; Aardema &

O’Connor, 2012) with preliminary evidence to show that the IBA to treatment

is effective in reducing OC symptoms to the same degree as cognitive-

behavioural approaches and to a better degree in particular OC presentations

(O’Connor et al., 2009). In addition, the relationship found between delusional

disorders and IC has provided impetus for the researchers to conceptualize

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OCD as a belief disorder (Aardema et al., 2005). However, there has only

been one research team to study IC in OC and delusional disorders (DD)

empirically and replication is required by other researchers.

From a review of the literature (O’Leary, unpublished), additional

evidence is needed in the area of IC, OC and DD. Given the largely

correlational nature of the current evidence, studies utilising ecologically valid

experimental paradigms to measure IC are needed. There are few studies that

have experimentally tested IC and OC and none that experimentally assess this

in addition to delusions. Therefore the aim of the current study is to

experimentally manipulate the process of IC and assess its relationship with

OC and schizotypy in a non-clinical sample. Aardema (2009) used a vignette

describing a situation to operationalize IC experimentally. In this paradigm,

the participant reads a scenario the conclusion of which leaves doubt about

whether an accident has occurred. The participant rates the probability that an

accident has occurred (i.e. doubt that it has not occurred). Then, subsequent

pieces of information are given with the aim of reducing or increasing doubt

about whether the accident has happened. This is an analogue doubt in OC

and is an operationalization of IC because it looks at reasoning following the

inclusion of reality and possibility based information.

The current study will also be assessing the role of dissociation in the

relationship between IC, OC and DD given that absorption into the imaginary

has been postulated by the IC theory as part of the IC reasoning process

(O’Connor et al. 2005).

Main Hypotheses Correlation

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Scores on a self-report measure of IC will be positively correlated with levels

of doubt in two computerised tasks.

Regression

Scores on IC, OC, schizotypy and dissociation will predict levels of doubt in

two computerised tasks.

Method

Participants

A non-clinical sample of 50 participants will be recruited for the

experiment. This sample size is deemed the achievable sample size for an

experimental design of this scale. For correlation analysis, a sample of 50 can

achieve a moderate effect size of r=.4 at 80% power for a two tailed

hypothesis (alpha .05). For the regression analysis with 4 predictors, 50

participants can achieve an effect size of R2=.20 - .26 at 80% power, with the

alpha at .05. Given that the experimental tasks will be conducted in a driving

simulator, participants will be aged 18 or over and must hold a valid driving

licence. The study will recruit students and non-students. The university’s

electronic participant recruitment system (Sona) will be used to advertise the

study and recruit students. Undergraduate psychology students will be able to

earn two lab tokens for their participation. All participants will be offered a

sweet to thank them for their time. A recent simulator study conducted by the

research supervisor recruited 44 participants over the course of 4 months, so

the target sample of 50 seems feasible in the proposed timeframe of data

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collection for this study. It might also be possible for assistance in testing to

be provided by a research apprentice working with the research supervisor.

Design

A mixed methods design is proposed, utilising a within participants

experimental design and a descriptive thematic analysis. For the experimental

aspect, the within participants IV is simulation condition and has 2 levels: OC

type simulation and delusional-type simulation. Order of presentation will be

counterbalanced across participants. The dependant variable will be the level

of doubt that is induced in each participant by each simulation condition.

Participants will also complete measures of IC, dissociation, OC and

schizotypy in order to examine the associations between these and levels of

experimentally induced doubt. Participants will be asked how much time they

spend playing video games to assess whether this has any bearing on the

outcome variable.

Apparatus

A STISIM Drive Build 2.08.05 driving simulator system connected to

a 1990 registered Rover Metro car mounted on axle stands will be used. 4

projector screens are connected to the car to achieve a rear view mirror image

and a panoramic wraparound road environment display. Mounted on both

door mirrors are TV cameras that give the driver rear and side views of the

driving environment. Drivers are monitored on a PC screen during the

simulation via a camera that is installed on the dashboard.There will be three

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driving simulations. One practice simulation lasting approximately 4 minutes

and two experimental simulations lasting approximately 9 minutes each. The

practice simulation will be an opportunity for the participant to familiarise

themselves with the driving controls and to check that they do not have a

simulator sickness reaction, in which case they would be advised to

discontinue with the study. The OC condition consists of a challenging driving

situation the result of which is the participant is left unsure whether they have

hit a cyclist or another road user. A key part of the simulation is that the

cyclist disappears from view. This is designed to induce doubt and the content

is related to a common OC concernsince it is focused on a common OC

experience and it includes the responsibility bias often seen in OC. A previous

study by the research supervisor using this simulation found that it induced

doubt about a collision in 98% of participants. The delusion simulation is

designed to induce doubt about whether the driver is being deliberately

pursued. In this simulation, a car stays behind the participant for the whole

journey despite having possible reason to overtake. This is related to

delusional experiences since it is based on a common persecutory delusional

experience. At the end of the simulation, the participant will be left unaware as

to whether the car behind was following them or not. Both simulations will be

piloted prior to the main study.

Measures (Appendix A)

The Inferential Confusion Questionnaire - Expanded Version (ICQ-

EV) (Frederick Aardema, Kevin D. Wu, Yves Careau, Kieron

O’Connor, Dominic Julien, & Susan Dennie, 2010) is a 30 item

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measure of IC, where each statement is rated on a 6 point scale from

strongly disagree to strongly agree. It has been shown to have excellent

internal consistency, with an English-speaking sample providing an

average item-total correlation of .66 (range .46 to .76) and a

Cronbach’s alpha of .96. Convergent, group criterion and clinical

validity has all also been demonstrated.

Dissociative Experiences Scale-II (DES-II) (Eve Bernstein Carlson &

Frank W. Putnam, 1986) is a 28 item self-report questionnaire, using

100mm continuums to scale each item measuring frequency of

dissociative experiences. This measure has been shown to have good

test re-test reliability and good split half reliability. Good internal

consistency and construct validity have also been indicated.

Obsessive Compulsive Inventory - Revised (OCI-R) (Edna B. Foa,

Jonathan D. Huppert, Susanne Leiberg, Robert Langner, Rafael

Kichic, Greg Hajcak & Paul M. Salkovskis, 2002) is an 18-item self-

report measure of OC. The intensity of OC experiences is rated on a 5-

point scale ranging from not at all to extremely. Excellent test re-test

reliability, excellent discriminant validity and satisfactory convergent

validity have been shown.

Magical Ideation Scale (MIS) (Mark Eckblad & Loren J. Chapman,

1983) is a 30-item true-false measure of psychosis proneness and

schizotypy.

Measuring induced levels of doubt: This follows from the design used

by Aardema (2009) to experimentally investigate IC and OC. In

Aardema’s study a written vignette was given to induce doubt whereas

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in the current study a more immersive experimental paradigm, the

simulations, will be used. After each simulation condition, the

participants will be asked to rate their anxiety and the probability that

they think the incident inferred by the simulations has happened, i.e.

that they caused an accident involving the cyclist or that they were

being deliberately followed by the car behind. Participants will then be

given a series of possibility and reality based information. A paper

sheet with three reality and three possibility-based pieces of

information will be presented in alternating order. The purpose of the

reality-based information is to confirm the idea that the inferred

incident did not occur, in attempts to reduce doubt. The purpose of the

possibility-based information is to negate the previous piece of reality-

based information and potentially induce doubt. This is relevant to the

IC theory, since it mimics the process, which is postulated to represent

the reasoning processes in OC. Participants will then be required to

rate the probability that the inferred incident occurred after each piece

of reality and probability information presented. This is to identify if

doubt has been manipulated and how this affects the participant’s

reasoning about what happened in the simulation.

Once participants have completed the two simulator conditions, they will

be asked some brief questions about their experience. This will be done with

the aim of assessing whether participants’ account of their reasoning processes

in relation to the two conditions are consistent with the sorts of reasoning

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processes postulated in IC theory. This material will undergo a descriptive

thematic analysis. The questions will be as follows:

You initially rated the probability of you hitting the cyclist with the car

as X and the probability of you being followed as X. What influenced

your ratings?

How did the various pieces of new information influence your

probability ratings?

Prompt: why do you think your ratings changed?

Prompt: did your reasoning change over time?

Prompt: did you become more sure of less sure about what you

thought happened in the simulation?

Do you notice this sort of reasoning in your everyday life?

How do you think you would respond if the situations were real?

Any other comments?

Procedure (Appendix B for flow chart)

Participants will be recruited through the Sona online recruitment

system and via posters displayed around University campus. Snowball

sampling from people who take part will also be used. The Sona system is

used to advertise the study and allows scheduling of testing sessions. On

arrival, the participants will be given an information sheet and consent form.

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The information sheet will inform the participant that the experiment is about

personality and driving performance as this will provide a rationale for their

completion of the measures. Participants will be encouraged to drive as well as

possible throughout the stimulation. They will also be informed that they can

withdraw from the experiment at any time without having to give a reason.

Each participant will complete the measures of IC, dissociation, OC

and schizotypy. Half of the participants will then do the OC simulation first

and half will do the delusion simulation first to control for order effects. Once

each participant has completed their first driving simulation, they will be

required to complete the corresponding measure of induced doubt. They will

then complete their second simulation and the corresponding measure of

induced doubt. All participants will be asked to vocalise the process during a

brief interview, which will be recorded with their consent. They will be

debriefed about the true nature of the study and rewarded with research tokens

and/or a sweet for their participation. The experiment is expected to last about

45 minutes. All procedures will be piloted and refined prior to main data

collection. This will be particularly important for the analysis of reasoning

process, in terms of refining the questions to be used in the brief interview.

Ethical considerations

Deception regarding the purpose of the experiment (necessary to avoid

demand characteristics). In the information sheet participants will be informed

that the experiment is designed to test the relationship between driving ability

and personality characteristics, when it is in fact about the relationship

between the levels of doubt they display and the measures completed. This

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small deception is not expected to cause distress and the true nature of the

research will be revealed once the measures and driving simulation have been

completed. A similar study conducted by the research supervisor with 44

participants similar to those who will be recruited in this study reported no

adverse effects from the deception. In fact, some participants commented

positively on the ingenuity of the experiment. An unexpected potentially

beneficial effect was that some participants reported that the simulator had

made them more aware of the need to use their mirrors in real driving

situations. While participants will be initially deceived about the nature of the

study, the information sheet given before participation will accurately explain

the procedures involved in the research, any foreseeable risks and discomforts

to the participant, the benefit of the research to society and the individual, the

length of time the participants will be expected to participate, their right to

withdraw at any time, the person to contact if they have any further questions

and that the study has a favourable ethical opinion by the university ethics

committee.

The debrief will explain what was being investigated and why. The

participants will be told that the information sheet had a cover story to conceal

the real purpose of the study and why and have any questions answered

honestly. They will also be given an opportunity to withdraw the data that they

have supplied.

Participant distress. Participants may become distressed by the nature

of the individual measures, the driving simulation or the brief interview. To

manage this, information regarding access to support services relating to the

information presented will be given to each participant.

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In general, any potential stress caused by this study will be no greater

than that expected in their ordinary life. However, it is known that the

simulator can cause nausea in people who suffer from motion sickness. The

information sheet and study advert will make this clear and suggest that

participants should not volunteer if they are likely to have this reaction. Also,

a series of medical exclusions will be given on all information as used in the

previous study by the research supervisor.

Confidentiality. All information will be treated as confidential.

Participant information will be anonymised and they will be informed of this

process. Participants will also be informed of by what means, where and for

how long any data they provide will be stored for.

Name of Ethics Committee: University of Surrey Ethics Committee: Faculty

of Arts and Human Sciences.

R&D Considerations

Name of R&D department:

.......N/A......................................................................................

Proposed Data Analysis

Data checking: the researcher will check Data for erroneous scores

being entered or missing data points.

Descriptive Statistics: SPSS will be used to calculate measures of

central tendency (means, median and mode), measures of variability

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(distribution and standard error) and measures of the shape of distribution

(kurtosis and skewness).

Inferential Analysis: Correlation and regression will be used to

investigate how participants’ levels of OC, schizotypy and IC predict the

levels of doubt induced by the experiment.

Descriptive Thematic Analysis: Data from the brief interview will be

coded according to themes relevant to the IC theory.

Service User and Carer Consultation / Involvement

At a service user a carer drop session, consultation about the projects aims and

design were sought. Their feedback has been considered in this proposal

(Appendix C).

Feasibility Issues

The main threat is recruiting a sufficient number of participants. A

recent simulator study conducted by the research supervisor recruited 44

participants over the course of 4 months. Of those who initiated the study

none dropped out due to simulator sickness or other reasons.

Dissemination strategy

The findings will hopefully be disseminated via journal publication and

conference presentation.

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Study Timeline

(Appendix D)

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quantification of doubt in obsessive-compulsive disorder. International

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confusion and obsessive beliefs in obsessive-compulsive disorder. Cognitive

Behaviour Therapy, 35, 138-147. 

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Todorov, C. (2005). Inferential confusion in obsessive-compulsive disorder:

The inferential confusion questionnaire. Behaviour Research and Therapy, 43,

293-308.

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quantification of doubt in obsessive-compulsive disorder. International

Journal of Cognitive Therapy, 2, 188-205. 

Aardema, F., Radomsky, A. S., O'Connor, K. P., & Julien, D. (2008).

Inferential confusion, obsessive beliefs and obsessive-compulsive symptoms:

A multidimensional investigation of cognitive domains. Clinical Psychology

& Psychotherapy, 15, 227-238.

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Psychopathol Behav Assess, 32, 448-462.

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Slade, P., & Popplewell, D. (1996). The factor structure of ‘schizotypal’

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compulsive disorder: A critical review. Clinical Psychology Review, 16,

729-773.

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S., & McEvoy, J. P. (2002). Sensory acuity and reasoning in delusional

disorder. Comprehensive Psychiatry, 43, 175-178. 

Grenier, S., O’Connor, K.P., & Belanger, C. (2010). Belief in the obsessional

doubt as a real probability and its relation to other obsessive-compulsive

beliefs and to the severity of symptomatology. British Journal of Clinical

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thought. Journal of Mental Health, 3, 31-49.

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O’Connor, K. (2009). Cognitive and meta-cognitive dimensions of

psychoses. The Canadian Journal of Psychiatry / La Revue Canadienne De

Psychiatrie, 54, 152-159.

O’Connor, K., Aardema, F., & Pelissier, M. (2005). BEYOND REASONABLE

DOUBT: Reasoning Processes in Obsessive-Compulsive Disorder and

Related Disorders. England: John Wiley & Sons, Ltd.

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compulsive disorder. Psychological Reports, 93, 227-232.

O'Connor, K., Koszegi, N., Aardema, F., van Niekerk, J., & Taillon, A.

(2009). An inference-based approach to treating obsessive-compulsive

disorders. Cognitive and Behavioral Practice, 16(4), 420-429.

O'Connor, K., & Robillard, S. (1995). Inference processes in obsessive-

compulsive disorder: Some clinical observations. Behaviour Research and

Therapy, 33, 887-896.Pélissier, M., &

O'Connor, K. P. (2002). Deductive and inductive reasoning in obsessive-

compulsive disorder. British Journal of Clinical Psychology, 41, 15-27. 

Pelissier, M., O’Connor, K.P., & Dupius. (2009). When doubting begins:

Exploring inductive reasoning in obsessive-compulsive disorder. Journal of

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Sellen, J. L., Oaksford, M., & Gray, N. S. (2005). Schizotypy and conditional

reasoning. Schizophrenia Bulletin, 31, 105-116.

Tsakanikos, E. (2004). Logical reasoning in schizotypal

personality. Personality and Individual Differences, 37, 1717-1726.

Wu, K. D., Aardema, F., & O'Connor, K.,P. (2009). Inferential confusion,

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Inference-based reasoning in obsessive-compulsiveness, delusions and schizotypy.

Literature Review

Year 1

April 2013

Word Count: 7,755

This review has been aimed towards publication in Clinical Psychology

Review, as this is a high impact journal (7.071) that aims to publish cutting

edge articles and advance the practice of clinical psychology. Since this

123

review has implications for the understanding of obsessive-compulsiveness,

classification and treatment of obsessive-compulsive disorder and delusional

disorders, Clinical Psychology Review is an appropriate source for researchers

and practitioners to be made aware of the empirical evidence in this area. If

not accepted by Clinical Psychology Review, an alternative Journal to aim for

publication in would be The Journal of Anxiety Disorders. This journal has an

impact factor of 2.965 and accepts review articles that contribute substantially

to current knowledge in the field of anxiety disorders, which this review does

via OCD.

124

Abstract

Obsessive-compulsiveness is seen on a continuum between traits held

by the non-clinical population and those with a clinically diagnosed obsessive-

compulsive-disorder (OCD). The same type of continuum is seen between

schizotypy in the non-clinical population and the clinically defined disorders

of delusions. Inferential confusion is proposed as a possible transdiagnostic

model that explains the reasoning process behind both of these phenomena,

reclassifies OCD as a belief disorder and promotes a novel cognitive approach

to the treatment of these disorders. This review critically evaluates 20studies

published between 1994 and 2012 that empirically investigate inferential

confusion and inference based reasoning in both obsessive-compulsiveness

and delusions. The evidence provides moderate to strong support for the

validity of inferential confusion as a construct present in obsessive-

compulsiveness, the explanatory power of inferential confusion as a theory of

reasoning processes in obsessive-compulsiveness and for an inference based

approach to treatment. While there is preliminary evidence for the presence of

the inferential confusion process in people who experience delusions, more

research is needed to support the notion that inferential confusion may explain

the delusional experience. This is since other reasoning styles such as the

jumping to conclusions bias, have a stronger evidence base in the

understanding of the experience of delusions. Additional research is needed to

further the understanding of the relationship between obsessive-

compulsiveness, delusions and inferential confusion.

125

Introduction

The relationship between obsessional doubt and delusions has

appeared in the literature for over 100 years. Knapp (1890) was one of the first

to review the literature in this area which had mostly been informed by case

studies and clinical observation. Obsessional doubt has long been considered a

feature of obsessive-compulsive disorder (OCD). OCD is characterised by the

presence of obsessions (persistent and recurrent thoughts, impulses or images

that cause distress) and/or compulsions (mental acts or behaviours that are

aimed at reducing distress) that are perceived by the individual as either

distressing, time consuming or disruptive to functioning (DSM IV, 2000).

Obsessive-compulsiveness is also seen in non-clinical populations and thus an

obsessive-compulsive continuum has been proposed, with diagnosable OCD at

the extreme end of this continuum (Gibbs, 1996).

O’Connor, Aardema and Pelissier (2005) propose a novel theory of

OCD that conceptualises it as a belief disorder. According to this theory,

obsessions are constructed as primary inferences of doubt about a possible

state of affairs that are influenced by unusual reasoning styles. In this theory, a

mental intrusion is an inference of doubt about reality that leads the individual

to distrust their physical senses in preference of this imaginary possibility

(O’Connor & Rollibard, 1995). An example of this would be, thinking that

one has left the cooker on. Subsequent compulsions fail to overcome the

primary doubt given that the individual is attempting to use reality to modify

the imaginary. An example of this would be, checking that the cooker is off.

Thus, the doubt is never resolved, only reinforced, and the cycle continues

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(O’Connor & Aardema, 2003). Due to the confusion noted between reality-

based and imaginary states of affairs, this theory of obsessive-compulsiveness

is coined Inferential Confusion (IC) (O’Connor et al., 2005).

IC theory was developed through observation of individuals diagnosed

with OCD and over-valued ideas (OVI) (Aardema, Emmelkamp & O’Connor,

2005). OVI are defined as near delusional beliefs (DSM IV, 2000) because

they lack the criterion of ego-dystonicity that applies to obsessive-

compulsiveness. Kozak and Foa (1994) found that the comorbidity of OVI in

obsessive-compulsiveness could moderate the strength of the obsessive-

compulsive belief so that it appears more akin to a delusion. In this way,

obsessive-compulsive phenomena and delusions have been linked

conceptually in the literature.

Delusions are defined as false beliefs despite evidence to the contrary

(DSM IV, 2000). Johns and Os (2001) reviewed research on the experience of

delusions in the non-clinical population, concluding that the experience of

delusions lies on a continuum. Unusual experiences such as delusions are part

of what is termed by Claridge et al. (1996) as schizotypy. Schizotypy is a way

of construing non-clinical delusional type beliefs that lie on a continuum with

the delusions that are referred to in clinically diagnosed disorders. If we

consider obsessive-compulsiveness and delusions together, unusual ways of

thinking about reality, that are not shared by others and that are causally

implausible and which lie on a continuum of severity, appear to characterise

both obsessive-compulsiveness and delusions. In the case of the latter, the

term schizotypy has been used to characterise non-clinical delusional

phenomena.

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What marks these two categories of phenomena apart appears to be the

presence of insight, with obsessive-compulsiveness considered ego-dystonic

and delusions ego-syntonic (Yaryura-Tobias, 2004). When OCD is comorbid

with OVI however, it seems that insight is reduced and the experience is more

ego-syntonic (Veale, 2002). OVI have been conceptualised as sustained

isolated beliefs, which are ego-syntonic and strongly held, yet with less

intensity than delusions (Veale, 2002). OVI have been suggested to act as

barrier between obsessions and delusions (Yaryura-Tobias, 2004), which

implies that OVI may be on the same continuum between obsessive-

compulsiveness and delusions. Schizotypy refers to the experience of

delusional thoughts or beliefs with or without OVI, and thus, insight could be

considered variable. Given the similarities between these concepts of human

experience, IC has been proposed to be a possible explanation of delusions as

well as obsessive-compulsiveness (Aardema, O’Connor, Emmelkamp,

Marchand & Todorovc, 2005). IC is therefore expected to be relevant to

obsessive-compulsiveness and OCD, delusional disorders and schizotypy, all

with or without OVI.

O’Connor (2009) proposes that IC may be one of the reasoning styles

that make fictional narratives seem so real in delusions and obsessive-

compulsiveness. Given that the main body of research on IC has been gathered

from studies on obsessive-compulsiveness, there is more literature in this area

than in the area of in delusions. This review will aim to evaluate the evidence

for the IC theory of obsessive-compulsiveness. It will also consider the current

evidence for this theory in delusional disorders and schizotypy. If supported,

there may be reason to further investigate IC as a possible trandiagnostic

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model across disorders. This would prove clinically advantageous as the

inference-based approach to treatment, could add to traditional cognitive and

behavioural treatments of obsessive-compulsive and belief disorders,

improving client choice and treatment variability.

Method

The literature search aimed to identify references that related to all

inference based reasoning in obsessive compulsiveness, delusional disorders

and schizotypy. A computerised search of the literature for all relevant articles

was performed using the databases, PsychINFO, Medline, Web of Science and

Scopus. The Boolean search terms used were: ‘inferential confusion’ OR

inference OR ‘reasoning process*’ AND obsess* compuls* OR schizotypy

OR delusion*. Inferential confusion was used as well as the word inference to

capture articles on the reasoning process termed inferential confusion and on

inference-based reasoning. Reasoning process* was also included to capture

any inferential reasoning processes that may have been named differently or

not at all. The term obsess* compuls* allowed the databases to search for

research both on the study of people diagnosed with OCD as well as those

measured on the continuum of obsessive-compulsiveness. Schizotypy was

used instead of schizo* to minimise the identification of the large body of

research conducted with people with a diagnosis of schizophrenia, as this was

not the focus of the current review. Delusion* was included to allow access to

studies in relation to delusional disorder or other delusional thought.

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There were no date restrictions placed on the original search, and the

search terms were identified in the abstracts of available materials. Reviews,

editorials, case studies, books, abstracts and dissertations were excluded, and

only peer reviewed journal articles written in English were considered. The

inclusion criteria consisted of empirical research on inferential confusion,

inference-based reasoning and reasoning processes that involved making

inferences in OCD, obsessive compulsiveness, schizotypy, delusional

disorders or delusions. Studies looking at schizophrenia rather than

schizotypy were excluded unless participants with a diagnosis of

schizophrenia were recruited for the purpose of studying delusions.

The search resulted in a total of 319 hits, 99 from PsychINFO, 53 from

Medline, 162 from Web of Science and 5 from Scopus. After accounting for

duplicates found across databases and evaluating the studies based on the

inclusion and exclusion criteria defined, 16 unique articles were selected. A

manual search of the reference lists of these 18 articles produced a further 4

articles not identified by the computerised search. The total sample was 20

articles all published between 1994 and 2012. See Appendix A for figure 1.

In this review, it may help focus to concentrate on the following: that

IC theory is a theory that has arisen and been most researched in OC, but that

this type of reasoning, as discussed, may be relevant to belief disorders.

This review presents evidence for the role of IC in OC and then goes

on to consider the relatively smaller evidence base on the relationship between

IC and delusional disorders or schizotypy. Overall, the review aims to

consider the relevance of the IC reasoning style for OC, schizotypy and

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delusional disorders, in order to consider implications for theory, research and

practice.

Results

The literature has been separated into the following subheadings;

Inductive and deductive reasoning in obsessive-compulsiveness; Inferential

Confusion and obsessive-compulsiveness; Inference-Based Approach to

treating obsessive-compulsiveness; and Inferential-based reasoning in

delusions and schizotypy. All of the research considered in this review is

quantitative as no qualitative studies were found in this research area based on

the search terms described above.

Inductive and deductive reasoning in obsessive compulsiveness

The authors of the IC model propose that OCD is an inductive

reasoning disorder. Of the studies found that focused on inference-based

reasoning styles in OC, one cross-sectional design aimed to understand the

differences between groups in inductive and deductive reasoning, while the

other quasi-experiment investigated inductive reasoning specifically (Pelissier

& O’Connor, 2002; Pelissier, O’Connor & Dupius, 2009). Differences in

inductive reasoning style would support IC theory because it is essentially a

theory that proposes that people with OC reason in different ways to those

without OC (O’Connor et al., 2005).

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Pelissier and O’Connor (2002) compared participants with OCD,

generalised anxiety disorder and a non-clinical control group (N=12, 10, 10

respectively) on a series of inductive and deductive reasoning tasks. When

compared on the deductive reasoning tasks, the 3 groups did not differ.

However, when comparing the groups on the inductive tasks, the OCD group

took longer to make inferences and seemed to express more doubt during the

tasks than the other groups. The authors speculate that people with OCD

create too many mental models during inductive reasoning tasks, which

increases their cognitive load resulting in slower performance and greater

doubt. Caution should be taken when generalizing these results due to the

small sample size and subsequent lack of statistical power. Also, it is not clear

whether the inductive reasoning tasks that were developed by the authors had

been tested for reliability or validity, so there may have been increased

chances of a type 1 error.

Pelissier et al. (2009) developed and validated the ‘Reasoning with

Inductive Arguments Task’ (RIAT) to measure the strength of inference in

inductive reasoning. They found that while all 74 participants in their quasi-

experiment doubted at the same level on the task, when the researchers

provided other possibilities for a conclusion to the task, those diagnosed with

OCD doubted significantly more than non-clinical control group, suggesting

that they generated more inferences from the given information. They

concluded that people diagnosed with OCD are more reliant on external

information to make inferences about a possible state of affairs. This is in line

with the IC theory, in that it supports the circularity of OCD. The compulsion

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of checking the cooker is off, which is reality based, is ineffective in

neutralizing the hypothetical inference that “maybe the cooker is on”, since the

hypothetical possibilities are endless (O’Connor, 2009).

In both of these studies, it might be suggested that the participant’s

level of intelligence could have been a confounding variable related to their

reasoning performance. To some extent, Pelissier et al. (2009) try to account

for this in that their participant groups did not differ on education level.

However, this may not be a valid proxy for intelligence therefore the findings

cannot be considered representative of only differing reasoning styles in these

groups. In addition to this, attention and memory biases that have been noted

in those with a diagnosis of OCD compared to those without (Muller &

Roberts, 2005), were not controlled for and hence, may have also been

accountable for some of the differences between the groups. While Pelissier

and O’Connor (2002) utilized an anxiety comparison group, neither study

included a mood or belief disorder group, meaning that it is not clear whether

the findings are in fact specific to anxiety or OC anxiety.

Inferential Confusion in obsessive-compulsiveness

Seven out of the 20 studies reviewed concentrated on the nature of the

relationship between IC and OC. These consisted of five correlational studies,

two that recruited non-clinical participants (Aardema, Radomsky, O’Connor &

Julien, 2008; Wu, Aardema & O’Connor, 2009) three with clinically

diagnosed participants (Aardema, O’Connor & Emmelkamp, 2006; Aardema

133

et al., 2010; Grenier, O’Connor & Belanger, 2010; Polman, O’Connor &

Hiusman, 2011;) and one quasi-experiment that compared clinical and non-

clinical participants (Aardema, O’Connor, Pelissier & Lavoie, 2009).

Batteries of questionnaires were administered to large samples of

undergraduate students (N=130, N=317) with the aim of investigating the

relationship between IC and OC (Aardema et al., 2008; Wu et al., 2009). Both

of these studies measured the presence and strength of six obsessive belief

domains, IC and OC thoughts and behaviour while controlling for anxiety and

depression. Before determining the relationships between the constructs,

Aardema et al. (2008) used factor analysis to define the underlying factor

structure of the combined OC beliefs and IC so that the overlap between

variables would be reduced. The result of this analysis was that IC/threat

estimation was analysed as a single variable.

Both studies demonstrated that IC/threat estimation or IC correlated

most strongly with OC symptoms, above all other measures. Aardema et al.

(2008) demonstrated the construct of IC/threat estimation to be the strongest

predictor for all OC subtypes, even when the OBQ subscales of responsibility

and threat estimation were controlled for, with effect sizes ranging from 0.36

to 0.57. Wu et al. (2009) discovered that the relationship between IC and OC

symptoms on all measures was not consistent across OC symptomology. The

ICQ-EV used to measure IC, significantly predicted checking and rituals such

as grooming, but not washing symptoms (Wu et al., 2009).

The highly correlated IC/threat-estimation factor and the

threat/responsibility subscale of the OBQ in the original study by Aardema et

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al. (2008) could be seen as a significant limitation (effect size = 0.74). It

implies that IC may be measuring the same phenomena as a pre-existing

cognitive domain, rendering it redundant. The authors addressed this weakness

by identifying that the overlap between IC/threat-estimation and the

threat/responsibility subscale was due to the tendency of people experiencing

OC symptoms to make threat related inferences on the basis of subjective

information. This overlap mirrors the IC theory, which postulates that IC and

cognitive explanations of OC, including OC beliefs, are complimentary

(O’Connor et al., 2005). While findings from non-clinical populations can

contribute to theory development for clinicians to draw on, these findings

required replication with individuals that are diagnosed with OCD, as it is not

clear if subtype differences would emerge in a clinical sample.

In a sample of 85 participants diagnosed with OCD, Aardema et al.

(2006) used correlational analysis to assess the relationship between OC

beliefs, OC symptoms, IC and anxiety. While controlling for the three

domains of the OBQ-44 that the ICQ correlated highly with, the relationship

between OC symptoms and IC remained significant (r= 0.43). Aardema et al.

(2010) also measured a large number of participants (N=100) with a primary

diagnosis of OCD on OC symptoms, IC, depression, anxiety and OC beliefs.

They compared the results with all measures in a non-clinical sample and an

anxiety control group. Their findings replicated the correlational analysis of

previous research in non-clinical samples (Aardema et al., 2008) in regards to

the moderate to strong relationship between and specificity of IC to OCD (r=

0.50, r=0.42 when mood controlled for). IC remained moderately correlated

135

with the responsibility/threat subscale of the OBQ (r=. 57), however this was

not considered to affect the construct validity of the measure, since the IC

remained significantly correlated with overall OC symptoms, when the OBQ

was controlled for (r = .40). A discrepancy in subtype specificity compared to

other studies occurred, with the results from this study suggesting that IC

significantly relates to harm thoughts, checking and contamination, when

controlling for obsessive beliefs (Aardema et al., 2010).

The small sample size of the anxiety control group in the cross-

sectional correlation could be considered a limitation of the methodology

(N=16). However, the ICQ-EV was able to differentiate between the anxious

and OCD group despite this inconsistency. The significance of the present

findings may have been enhanced by the large sample size for the OCD group

(N=100) and the non-clinical control group (N=550). Aardema et al. (2010)

found a moderate correlation between the ICQ-EV and negative mood states,

suggesting that mood and anxiety may account for some of the relationship

between IC and OC. When controlling for negative mood and OC beliefs, the

ICQ-EV no longer related to the grooming and dressing compulsions and

obsessional impulses of harm to self or others subscales. Aardema et al. (2010)

attribute this finding to the inadequacy of OCD measure used in the study.

While they present good argument for this, it highlights the disadvantages of

using questionnaires to measure socially defined human phenomena.

Polman et al. (2011) assessed OC beliefs and symptom severity in 174

participants with a diagnosis of OCD. Cluster analysis revealed that a

substantial number of participants from this sample, between 38.4% and

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64.5%, could be classified as a low obsessive belief subgroup. This meant that

they scored low on the obsessive beliefs questionnaire, which had been

previously shown to predict OC symptoms. Participants from this low belief

group did not significantly differ in IC from the high belief subgroup of

participants. The high belief subgroup was comprised of those participants that

scored highly on the obsessive beliefs questionnaire, as you would expect

somebody with a diagnosis of OCD to do. Since the high and low obsessive

belief groups did not did differ on OC symptom severity or levels of IC, the

results from this study demonstrate the presence of IC in OC without

obsessive beliefs, regardless of symptom severity. This highlights IC as

statistically, significantly and independently related to OC. The authors

interpret their findings to challenge criticism regarding the impact of the

overlap between IC and obsessive beliefs, particularly the overestimation of

threat, in that IC is a separate experience to the overestimation of threat belief

that someone with OCD may have.

Each study differed in the measures used to tap the constructs included

in their analysis. See Appendix B for table 1. In spite of this, the variation of

measures used was not that wide spread. Utilising additional questionnaire

measures as well as using experimental methods to quantify the constructs

investigated in these studies may make for a more reliable and generalizable

evidence base.

Grenier et al. (2010) collated cross-sectional and longitudinal data

from three separate experiments previously conducted in the same research

centre (O’Connor et al., 2005; O’Connor et al., 2006; O’Connor et al., 2009).

In support of the IC theory, they found that all 108 participants diagnosed with

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moderate-severe OCD, were able to identify a primary inference of doubt.

Correlational analysis showed that the consequence of not acting on the doubt,

for example, the house will catch fire, was made more realistic by the strength

of belief in the probability of the content of the doubt occurring, such as,

“maybe I have left the cooker on”. The stronger the belief in the probability of

the content of the doubt occurring, the weaker the participants perceived their

ability to resist their compulsive behaviour, checking that the cooker is off.

Perceived ability to resist compulsions was significantly negatively related to

anxiety and obsessive symptom severity. This suggests that strength of belief

in the probability of the content of the doubt occurring relates to the severity

of the OC symptoms. In all of these analyses, medium to large effect sizes

were found in the range of 0.22 - 0.47.

Hierarchical regression analysis further showed that perceived ability

to resist compulsions was independently and significantly predicted by

strength of belief in the probability of the content of the doubt occurring,

whereas realism of anticipated consequences of the doubt occurring did not

significantly independently predict perceived ability to resist compulsions.

This suggests that the belief in the primary inference of doubt occurring might

better explain OC than the secondary appraisal or anticipated consequences

that are proposed in cognitive-behavioral models. This supports O’Connor et

al.’s (2005) proposal that IC is the primary process in obsessions with

appraisal of consequences being secondary to this. While this study

demonstrates the relationship between doubt and OC, it does not show the

direction of such a relationship, and therefore IC cannot be supported as a

generator of OC symptoms. This is since alternative conclusions can still be

138

made, i.e. that OC might cause higher levels of doubt in those diagnosed with

the disorder.

Quasi-experimental research by Aardema .. (2009) compared

participants with a diagnosis of OCD to a non-clinical control group, in a

reasoning task designed to measure levels of doubt in response to possibility

and reality based information. According to IC theory, people with OCD

should doubt more than those without OCD when presented with possibility-

based information. This is since the experimental paradigm is designed to

emulate the occurrence of obsessive-compulsive-like hypothetical inferences

towards which people with OCD are proposed to respond to with greater

doubt. As predicted, doubt in those with OCD was higher than that in the non-

clinical group when presented with possibility-based information. There was a

strong relationship between the levels of doubt and OC symptom severity,

further supporting the IC theory in he notion that doubt and OC symptoms are

linked. As with Grenier et al.’s (2010) study however, these results do not

conclude that IC predisposes OC as speculated by the IC theory, since it may

still be that having OC distorts ones reasoning processes or that a third

variable is responsible for the IC/OC relationship, something that cannot be

falsified due to the quasi-experimental design.

Since alternative conclusion can be made about the direct of the

relationship between IC and doubt and OC symptoms, more longitudinal and

studies are needed to enhance the developmental understanding of the IC/OC

relationship. In spite of that, current knowledge provides strong evidence for

the IC theory’s premise of the importance of the initial doubt in OC. Given

that the comparisons studies presented here only include OC and non-OC

139

groups, it in turn remains an empirical question whether this type of reasoning

style may be evident in other clinical presentations.

Inference-Based Approach (IBA) to treating obsessive-compulsiveness

The IBA is the intervention that was developed based on the IC

theory. Therefore, studies investigating the effectiveness of IBA can add

support to IC theory. Three quasi-experiments investigated the effectiveness of

CBT and IBA for OCD (Aardema, Emmelkamp & O’Connor, 2005; Aardema

et al., 2010; Aardema & O’Connor, 2012) and one randomised controlled

experiment (O’Connor et al., 2009) explored the efficacy of IBA in

comparison to other cognitive-behavioural treatments for OCD.

35 participants from Aardema et al.’s (2005) quasi-experiment

received 20-sessions of individual CBT for OCD, with the aim of investigating

the effect of change in OC symptoms on IC. Paired sample t-tests showed on

average there was significant reduction in their OC symptoms, anxiety and

depression scores. IC, primary inference and secondary inference, as measured

by clinical interview, were all also significantly lower post-treatment

(p<0.001). 19 participants whose scores improved by 33% from pre-treatment

to post-treatment, they were classified as responders and the remaining 11

were classified as non-responders. While the two groups of responders and

non-responder did not significantly differ in the amount their IC scores

changed, there was less change in IC scores for non-responders, compared to

responders. Pearson’s r correlations demonstrated that change in IC score was

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significantly related to change in OC symptoms scores overall, on two

different measures (r= 0.44, r= 0.46). By dichotomising the group into

responders versus non-responders there is a reduction in statistical power.

Aardema et al. (2010) selected 38 participants from their original

sample of those diagnosed with OCD to investigate the effects of inference-

based-therapy (IBT) on OC symptoms. T-tests showed that after IBT, OC

symptoms significantly reduced to a mild level on two measures. OC beliefs

as well as negative mood states decreased to that seen in non-clinical control

groups and while IC reduced, it remained higher than seen in the non-clinical

control group. All differences in scores were significant to the 0.001 level. The

participants were dived into responder and non-responder groups based on a

30% improvement rate in OC symptom scores. Individual t-tests demonstrated

that responders and non-responders could only be significantly differentiated

by improvement on the OBQ subscale responsibility/threat and the ICQ-EV,

both at the 0.05 confidence level (Aardema et al., 2010).

Limitations of Aardema et al.’s (2010) study are the lack of

information regarding how the 38 participants from the larger sample were

chosen to take part in IBT. Selection bias may have caused regression to the

mean, which could have enhanced the efficacy of IBT. Endogenous change

and expectancy effects could have been responsible for the success rates of the

treatment in either study and so more research is needed into IBA to see if

effect sizes are supported across studies.

Aardema and O’Connor (2012) evaluated the outcome of a 24-week

IBT in 35 participants, diagnosed with OCD. Paired t-tests showed significant

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decreases on two measures of OC symptoms post-treatment (Cohen’s d = 2.15

and 1.06), as well as a significant improvement in anxiety (Cohen’s d = 0.58)

and depression scores (Cohen’s d = 0.79). There was a significant reduction in

IC and in participants’ ability to resolve doubt by the end of treatment

(Cohen’s d = 0.63). Based on a measure of doubt resolution, the authors

classified participants into one of three groups. ANOVAS showed that

resolution, pre-resolution and no resolution groups all experienced a

significant reduction in OC symptoms but that the resolution group improved

the most on IC scores. Results confirm that IBT produces significant

reductions in IC, obsessionality and negative mood states, while making

significant improvements in the ability to resolve doubt. Even with a small

sample size, this study provides support for the IBA to treating OC. Findings

did show however, that a quarter of the participants who could not resolve

doubt at the beginning of treatment still could not resolve it at the end,

suggesting that IBT was not universally effective. In spite of this symptoms

still reduced, which suggests that the IBA can produce change in OC

symptoms even when participants cannot resolve doubt. This implies that IBA

might be a general treatment model for distressing symptoms in other

disorders that do not involve the initial doubting process outlined by the

authors of IC theory in OC.

O’Connor et al. (2009) conducted a randomised control trial to assess

the efficacy of IBT. Participants with OCD were randomly allocated to one of

three treatment groups. 16 participants received an IBA, 16 received a

Cognitive Appraisal Model (CAM) treatment and 12 received Exposure with

Response Prevention (ERP). Results showed that the three treatments were

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equally efficacious in reducing OCD scores. Therapist, treatment integrity,

motivation, dropouts, model integration and client satisfaction were all well

controlled for. All participants’ scores decreased significantly on OC

symptoms with no treatment by group effects. The effect size for Y-BOCS

was 0.68 and 0.57 for the PI. When those with a significantly high belief in

their primary inference of doubt were analysed, greater improvements were

shown by the IBA to treatment over the CAM on both measures of OC

symptoms (ERP was excluded due to low primary inference scores at pre-

treatment). Duration and distress equally significantly reduced in all treatment

groups, with cognitive intrusions showing a trend of better outcome in the IBA

group as opposed to the CAM and ERP groups. Levels of depression

significantly reduced in all groups with a significantly better outcome for

depression in the IBA group. Anxiety did not significantly reduce in all

groups, but did significantly reduce in those with a high primary inference

conviction in the IBA and CAM groups, with no treatment by effect

interaction. These results suggest that the IBA may be as effective as current

CBT in treating OC symptoms and more effective for those who have a strong

belief in their primary inference of obsessional doubt. However, it is important

to note that the ERP group had lower belief in primary doubt at the beginning

of the trial, suggesting that the IBA groups’ reduction in scores may have been

increased by regression to the mean, since the IBA group were working on

primary doubt in participants who originally scored higher on this measure. A

further limitation is the lack of placebo or control group to provide maximum

contrast with the therapies evaluated. This may have been due to ethical issues

regarding withholding effective treatment. The better treatment outcome

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observed here in those with OCD and OVI promotes the possibility that IC

may account for OVI in delusions as well.

Inferential-based reasoning in delusions and schizotypy

Eight of the studies reviewed focus on the relationship between IC,

OCD, delusional disorder and schizotypy. One cross-sectional study and three

quasi-experiments focus on reasoning in OCD and delusional disorder (DD) in

clinical samples (Aardema et al., 2005; John & Dodgson, 1994; Conway et al.,

2002; Fear & Healy, 1997). Two quasi-experiments and two correlational

studies utilize non-clinical samples to investigate reasoning in schizotypy

(Jacobson, Freeman & Salkovskis, 2012; Sellen, Oaksford & Gray, 2005;

Tsakanikos, 2004; Aardema & Wu, 2011).

Aardema et al. (2005) used questionnaires to measure IC, OC beliefs,

OC symptoms, thought-action-fusion, anxiety and depression in 85

participants with OCD, 31 participants with other anxiety disorders, 16

participants with DD and 51 non-clinical controls. Analysis showed that

participants with OCD scored significantly higher on IC than the participants

with anxiety and the non-clinical controls, as did the participants with DD (p<

0.05). There were no significant differences between the IC scores of the

participants with OCD and those with DD. Interestingly, IC in the DD group

was significantly related to all subscales of the OC symptoms measure,

whereas IC in the OCD group was only significantly related to overall OC

symptoms severity and three of the subscales; thoughts about harm,

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contamination and checking (p< 0.05). The participants diagnosed with

anxiety did not show any significant relationship between their scores on IC

and OC symptoms. This highlights the possibility that IC may be more

relevant to belief disorders than anxiety disorders and indeed, the authors

interpret these findings as support to conceptualize OCD as a belief disorder.

However, participants diagnosed with DD also reported more OC symptoms

than the other non-OC groups, perhaps indicating that the classification of this

group as having primarily DD was questionable.

Probabilistic reasoning tasks have been used in quasi-experiments to

investigate reasoning in DD (Conway et al., 2002; Fear & Healy, 1997). One

such task, originally devised by Garety, Hemsley and Wesseley (1991),

requires participants to draw beads one at a time from a jar in order to allow

them to estimate the proportion of beads of different colours in the jar to

decide on the colour status of jar. The jars contained different ratios of two

different colour beads and so participants had to use probabilistic reasoning to

make a judgement. John & Dodgson’s (1994) quasi-experiment was based on

the same principles, but used familiar contextual stimuli to enhance ecological

validity. Their reasoning task was a game of 20 questions, in which

participants (12 people experiencing delusions, 12 people with depression and

12 non-clinical participants) had to judge whom the researcher was thinking of

by asking up to twenty questions that would elicit a yes or no answer. John

and Dodgon’s (1994) data showed that people experiencing delusions

requested significantly less information when coming to a conclusion. Conway

et al. (2002) used a probabilistic task to demonstrate the same findings while

controlling for intelligence, sensory and neurological deficits, in the

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comparison of 10 participants diagnosed with DD and 10 non-clinical control

participants. The findings from both of these studies suggest that participants

with DD jump to conclusions when making inferences about a possible state

of affairs, sooner and with less information to make that conclusion than

participants who without DD. The authors of both these studies discuss

jumping to conclusions (JTC) as an unusual style of reasoning not dependent

on material presented (John & Dodgson, 1994; Conway et al., 2002). For all of

the research that has used the probabilistic tasks to assess reasoning style in

DD, the motivation, understanding and premorbid personality characteristic of

the participant group may have confounded the significance of findings (John

& Dodgson, 1994).

The opposite trend has been found in studies that investigate the JTC

reasoning style in OC. This is significant since the IC theory proposes that

reasoning in OC and DD might be similar, however, the JTC reasoning style

seen in DD appears different to the IC style of reasoning seen in OC. In cross-

sectional comparisons of people diagnosed with OCD, anxiety and non-

clinical controls, participants with OCD required near significantly more

information to come to a decision (p< 0.06) (Pelissier & O’Connor, 2002). In

comparing the performance of people with OCD to people with DD, Fear and

Healy (1997) replicated this finding in participants with OCD (N=29)

(p<0.0001) when compared to a group of participants diagnosed with DD

(N=30). In addition, they concluded that the reasoning style of those in a

mixed disorder group (OC and delusions, N=16) was closer to the non-clinical

norm than either the delusional group or the OCD group. Not only do these

findings support the idea that reasoning processes in OCD and DD are

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qualifiedly different from non-clinical reasoning, but also that they are

different from each other. The between group differences in age of onset of the

OCD and DD groups limit the internal validity of the task, as did the higher

Maudsley assessment of delusions schedule score of the group diagnosed with

DD compared to the mixed diagnosis group (Fear & Healy, 1997).

Jacobsen, Freeman & Salkovskis (2012) separated 32 participants

diagnosed with OCD into two groups of those with either high or low

conviction in the strength of their obsessive beliefs, and compared their

performance on a reasoning task with 16 participants currently experiencing

delusions and 16 non-clinical controls. This was to ascertain if conviction

levels are what accounts for the distinction between reasoning in obsessive

compulsiveness and reasoning in delusional thought. Order and practice

effects were controlled for, as was IQ. The probability inference task showed

no significant difference in the JTC reasoning style between the OCD high and

low conviction groups. The researchers inferred from this that while

conviction levels in OC can be equal to that of the conviction seen in

delusional thought, the reasoning processes underlying them is different. In

this study the OCD group was split into high and low conviction level groups

based on scoring in the top and lowest 50%. Differences between these groups

may not have been significant since what the researchers classified as high

scorers were relative to the participant groups scores, which may not have

been that high in conviction generally and therefore the high group may not

have represented conviction in obsessive beliefs as high as it can be seen, high

enough to be considered delusion like. Jacobsen et al. (2012) did not replicate

the differences in JTC between the groups diagnosed with delusions and the

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non-clinical control group, that has been found in previous research (John &

Dodgson, 1994; Conway et al., 2002; Fear & Healy, 1997). This may have

been a type 2 error due to small sample size since the trend was in the

expected direction but not significant.

Sellen, Oaksford & Gray (2005) measured 64 non-clinical participants

on schizotypy (O-LIFE) and a logical reasoning task. Those with higher

shizotypy scores evidenced greater JTC reasoning on the logical reasoning

task, with the subscale impulsivity/non-conformity predicting participants

performance. In an almost identical designed study by Tsakanikos (2004), the

negative schizotypy subscale was found to be the most reliable predictor of

logical reasoning deficit, in a non-clinical sample of 205 participants.

Aardema et al. (2006) measured on IC, schizotypy and OC in a non-

clinical sample of 108 participants. Results showed that the IC and schizotypy

scores were both significantly related to OC. Multiple regression analysis

showed IC and schizotypy both predicted unique variance in OC while

controlling for neuroticism (Aardema et al., 2006). Using a larger sample size

and controlling for negative mood state, these results were replicated by

Aardema and Wu (2011). Questionnaires were used to measure OC symptoms,

IC, schizotypy and other imaginative processes in 377 non-clinical

participants. Most of these measures correlated highly enough with each other

to emphasize the positive relationship between the constructs, without being

so high as to render any of them redundant. While all measures where

significantly related to the OC symptoms, IC (.58), schizotypy (.42) and

absorption in dissociative experiences (.41) showed the strongest correlations.

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The above studies are limited by their cross-sectional and quasi-

experimental designs that do not allow for causality to be inferred. The

correlational analyses do not allow for directional conclusions to be made and

the use of non-clinical samples limits generalizability of the findings to

clinical samples. The lack of comparison group in the latter studies (Aardema

et al., 2006; Aardema & Wu, 2011) also prevents further understanding of the

specificity of IC, versus its potential transdiagnostic properties.

Discussion

The present review aimed to provide an overview of the empirical

evidence for the role of IC in OC and delusions. The main findings and

limitations of this body of research will be discussed, ending with future

implications for theory, practice and research.

Summary of Findings

Overall, the evidence reviewed suggests that IC is consistently found

to correlate positively and significantly with OC symptoms and that it emerges

as an independent predictor of OC symptoms when controlling for OC beliefs,

mood and anxiety. The degree of IC is significantly related to OC symptom

severity and it has been demonstrated to explain some of the relationship

between doubt and OC (Aardema et al., 2008; Wu et al., 2009; Aardema, et

al., 2006; Polman et al., 2011; Grenier et al., 2010; Aardema et al., 2009;

Aardema et al., 2010). There is some moderate support for the differences in

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inductive and probabilistic reasoning in OC (Pelissier & O’Connor, 2005;

Pelissier et al., 2009; Fear & Healey, 1997) and delusions and schizotypy

(John & Dodgson, 1994; Sellen et al., 2005; Conway et al., 2002; Tsakanikos,

2004), supporting the initial premise that the IC theory for OC is based on, and

providing a complimentary or counter explanation to reasoning in delusions.

The IBA to treating OC symptoms has been supported (Aardema et al., 2005;

Aardema et al., 2010; Aardema & O’Connor, 2012) with preliminary evidence

to show that the IBA to treatment is effective in reducing OC symptoms to the

same degree as cognitive-behavioural approaches and to a better degree in

particular OC presentations (O’Connor et al., 2009).

The findings from this review also suggest that IC is more related to

specific subtypes of OC symptoms; obsessions about harm and washing

(Aardema et al., 2006), checking and grooming rituals (Wu et al., 2009) and

harm thoughts, checking and contamination (Aardema et al., 2010). The

information regarding the specific subtypes that IC may be more or less

related to varies between studies and while the IBA is successful in treating

OC symptoms whether OVI are present or belief in initial doubt left

unresolved (Aardema & O’Connor, 2011), it may be more helpful to consider

IC as a general model of OC rather than match it to symptoms subtype.

A transdiagnostic model?

It seems the relationship found between DD and IC provides

preliminary evidence to support the conceptualization of OCD as a belief

150

disorder (Aardema et al., 2005). One of the main limitations of Aadema et

al.’s (2005) study however, was the heterogeneity of the participants within

the OCD group. This may have been the reason that some subscales of OC

symptoms did not significantly relate to IC. IC therefore, may measure

underlying processes of OCD that are more attuned to schizotypy, rather than

be a transdiagnostic model for OCD and all belief disorders. Despite the need

for clarity, Aardema et al. (2005) have been the only research team to study IC

in OC and DD empirically. The larger body of knowledge for reasoning in

delusions lies with the JTC explanation (John & Dodgson, 1994; Sellen et al.,

2005; Conway et al., 2002; Tsakanikos, 2004). IC and JTC as explanations of

different human phenomena have some similarities in that they both frame the

respective disorders as arising from a lack of using ones senses to come to a

conclusion.

Jacobsen et al. (2012) interpret their results as verification of OCD as

an anxiety disorder, which should not be re-categorised as a belief disorder

even if conviction is akin to that seen in delusions or OVI. They also state that

transdiagnostic models of obsessions and delusions are not evident. This

research however only illustrates that the JTC reasoning bias seen in delusions

is not present in OC, it does not consider the presence of IC, so heavily

implicated in OC, as a reasoning bias in delusions. Thus, the possibility of IC

as a transdiagnostic model for both OC and delusions has not been falsified by

current findings. Overall, it seems that the conceptualisation of IC as an

explanation for belief disorders is more speculative than would have been

originally thought based on reviews by the originators of the IC theory

(O’Connor, 2009). The preliminary empirical work that has brought

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obsessive-compulsiveness, delusions and schizotypy together under the

explanation of inferential-reasoning processes (Aardema et al., 2006), suggests

that much more investigation is needed before IC can be considered a

transdiagnostic model of reasoning in OC and belief disorders.

To further quantify the trandiagnostic properties of the IC theory,

research has been conducted into other OC spectrum disorders, where beliefs

are more akin to delusions or overvalued ideas, given their ego-syntonicity.

Body-dysmorphic disorder and hoarding have both been shown to be

positively responsive to the IBA to treatment, suggesting that IC theory could

explain the unusual reasoning also seen in these disorders (Tallion, O’Connor,

Dupuis & Lavoie, 2013; St-Pierre-Delorme, Lalonde, Perreault, Koszegi &

O’Connor, 2011), supporting the IC theory’s position as a possible

transdiagnostic model for disorders on the continuum of OC, OVI and

delusions.

Limitations of studies reviewed

The inconsistency between correlations of specific subtypes of OC

with IC across studies questions the validity of the findings reviewed. The

discrepancy could have been due to the use of different IC measures (ICQ and

ICQ-EV), given that the ICQ-EV has been shown to have higher internal

consistency (.96 Conbrach’s alpha) than the ICQ and less overlap with

subscales of the OBQ (Aardema et al., 2010). This limitation could also have

been as a result of the heterogeneity of OC phenomena. The varying

presentations of OC symptoms will have affected the prevalence of subtypes

152

in each study and thus the outcome of subtype correlations. Screening for

specific subtype of OC within and across studies could help to control for this

effect, however findings from studies that select homogeneous participants

would be less generalizable to OC phenomena as a whole. In addition, the

screening out of participants with co-morbid disorders occurred in most of the

studies reviewed. While this was in effort to portray the specificity of IC in

OC, it reduced the ecological validity of most of the findings since it is not

representative of the high co-morbidity seen in those with a diagnosis of OCD

(Weissman et al., 1994). Defining OC based on the underlying mechanisms

defined by factor analysis, as opposed to the varying subtypes, may be a more

clinically relevant as it explains the functionality of the symptoms, which

could enable a more specific choice of treatment for those who have been

diagnosed with OCD (Polman et al., 2011).

Since most of the research in this area used the same OC symptoms

and general distress measures (See Appendix B, Table 1) variability of

measures may make for more experimentally valid and reliable results that can

be better generalized. Most of the research utilized a cross-sectional (Pelissier

& O’Connor, 2005; Aardema et al., 2008; Wu et al., 2009; Aardema et al,

2006; Polman et al., 2011; Grenier et al., 2010; Aardema et al., 2005;

Aardema & Wu., 2010; Jacobsen et al., 2012) or quasi-experimental design

(Pelissier et al., 2009; Aardema et al., 2009; Aardema et al., 2005; Aardema et

al., 2010; Aardema & O’Connor, 2012; John & Dodgson, 1994; Conway et al.,

2002; Fear & Healy, 1997; Sellen et al., 2005; Tsakanikos, 2004), the

statistical remits of which do not allow for accountability to be given to IC as

a theory of reasoning processes that causes obsessional doubt and therefore

153

OC. There is also a distinct lack of controlled experiments to enable any cause

and effect to be implied between IC and OC, IC and delusions and IBA in

treating belief disorders as well as OCD. Qualitative data was not apparent and

so as it stands, there is no empirical knowledge on the individuals experience

and perception of IC, whether in OC or delusions. There are only case studies

to represent this (O'Connor, Koszegi, Aardema, Niekerk, & Taillon, 2009).

Due to the content of research in this area thus far, there is currently no

understanding of how trauma, culture, society, family, attachment and

parenting may influence the presence and development of IC in either OC or

delusions. One of the most notable limitations to the research is that the

evidence presented to support IC in OC mostly emanates from the same

research team who devised the theory, which may have affected the objectivity

of their findings. Therefore, replication of the findings in this review by other

research teams is needed.

Future directions and implications

Additional evidence is needed in the area of IC and OC, IC and

delusions and IBA to treating OC, delusions and other belief disorders or OC

spectrum disorders such as OVI, BDD, hoarding, hypochondrias, anorexia

nervosa and trichotillomania. Studies should use ecologically valid

experimental paradigms to measure IC, be randomly controlled, include

individuals with co-morbid diagnoses and make comparisons with non-clinic

groups and no therapy variables. Further research should be considered to

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allow for a greater understanding of the context that IC develops in and how

this interacts with the presentation of symptoms that could be diagnosed as

either a belief or anxiety disorder. More research into the difference between

belief and anxiety disorders would be interesting in investigating the

transdiagnostic properties of the IC theory, as would research into the presence

of IC in those with no diagnosable symptomology. Dismantling studies would

allow for the understanding of what components of the IBA approach are

beneficial to which OC or delusional experiences. O’Connor et al. (2009)

suggest that the IBA approach would be beneficial for children and

adolescents, given that it may be easier to understand than other cognitive-

behavioural approaches to OC. Research investigating IBA in young people

would be beneficial as the potential is for it to be used as an early intervention

for children who may be distressed by OC or delusional experiences.

155

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Appendices

163

Appendix A

319 records were identified

through database searching;

PsychINFO, Medline, Web of

33 records were screened using

exclusions/inclusions criteria of

article type

254 records were excluded

319 records were screened using

exclusion/inclusions criteria of

article subject

33 records after duplicates

removed

17 records were excluded

(abstracts, thesis, case studies,

editorials)

4 records identified from manual

search of remaining 16 articles

Identification

Identification

Eligibility

Eligibility

Screening

164

Appendix B

Table 1. Summary of measures used in studies presented in review

Measures References of studies that used this measure

Padua Inventory Washington State University Revision (PI-WSUR)

Aardema et al. (2008), Wu et al. (2009), Aardema et al. (2006), Polman et al. (2011),

Vancouver Obsessional Compulsive Inventory (VOCI)

Aardema et al. (2008),

Inferential Confusion Questionnaire 15 Aardema et al. (2008), Aardema et al. (2006), Polman et al. (2011),

Schedule of Compulsions, Obsessions and Pathological Impulses (SCOPI)

Wu et al. (2009), Aardema & Wu. (2011),

Obsessive Compulsive Inventory Revised (OCI-R)

Wu et al. (2009),

Inferential Confusion Questionnaire Expanded (ICQ-EV)

Wu et al. (2009),

Beck Anxiety Inventory (BAI) Aardema et al. (2008), Aardema et al. (2006), Polman et al. (2011),

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Beck Depression Inventory (BDI) Aardema et al. (2008), Polman et al. (2011),

Mood and Anxiety Symptoms Questionnaire (MASQ)

Wu et al. (2009),

Obsessive Beliefs Questionnaire 44 Aardema et al. (2008), Wu et al. (2009), Aardema et al. (2006), Polman et al. (2011),

Yale Brown Obsessive Beliefs Questionnaire (YBOCS)

Polman et al. (2011),

Thought Action Fusion Questionnaire (TAF) Aardema et al. (2005),

O-LIFE Sellen et al. (2005),

The Schizotypal Syndrome Questionnaire Aardema et al. (2006), Aardema & Wu. (2010),

Aardema & Wu (2011),Dissociative Experiences Scale Aardema & Wu. (2011),

166

Adult Mental Health – Community Mental Health Recovery Service (CMHRS)

I used Cognitive Behavioural Therapy (CBT) and Narrative Therapy (NT)

individually with adults aged 18 to 65 years old with a range of enduring, severe,

mild, transitional and psychosocial problems. I also worked with acute presentations

as part of a family therapy clinic, offering systemic interventions to individuals,

couples and families on an adult mental health ward. I conducted two

neuropsychological assessments and worked with clients from a range of ethnic,

cultural, social and religious backgrounds. I used standardised measures and gathered

information from care-coordinators, general practitioners, ward staff and clinical

records. I conducted on-going risk assessment and implemented risk management

plans. I provided teaching to ward staff on genograms and I attended regular multi-

disciplinary team (MDT) meetings. I engaged with service users outside of the

clinical setting by attending the local Service User Engagement Network meeting.

Older People – Older people’s Community Mental Health Team (OPCMHT)

I worked therapeutically with individuals and couples with a wide range of enduring,

severe, mild, transitional, biological and psychosocial problems, between the ages of

66 and 89 using CBT and systemic therapy in either the OPCMHT base, on a physical

health ward or in the client’s home. I co-facilitated psychoeducational groups, a

continuous mindfulness group and a ten-week cognitive stimulation therapy group. As

part of the memory clinic, I completed a dementia assessment, which included

administering a battery of neuropsychological tests. I also used cognitive and memory

screening tools on several occasions. I worked with clients with severe memory

problems and those with physical disabilities. I provided supervision for an assistant

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psychologist and consulted to the staff team. I worked with another trainee clinical

psychologist to develop a new referral pathway for psychology groups.

People with Learning Disabilities – Community Learning Disabilities Team (CLDT)

I worked therapeutically with individuals with mild to severe learning disabilities and

mental health problems such as low mood and anxiety. I also completed two dementia

assessments for older men with downs syndrome. I conducted challenging behaviour

assessments and helped to create and implement positive behavioural support

programmes. I conducted this work in a range of settings including the team base, the

client’s homes and community centres. I worked independently and jointly with other

psychologists and members of the MDT. I consulted with staff teams, carers and

families.

Specialist Placement – Charity Project

I worked therapeutically in a third sector organisation with young men aged between

15 and 30 years old who were either offending or at risk of offending and may have

had an unmet mental health needs. This charity project was based in the local

community of the young people it served. The clients were referred by peers and

utilised the service on a drop in basis. I worked with young people who were assumed

to be from a socially disadvantaged social background, most of who were black

British, Caribbean or African. As a team we used a model that emphasised

metalisation as the main therapeutic approach. I also worked on engaging young

people with the service, helped them set goals, provided access to

education/employment/community, provide psychoeducation on mental and physical

health and encouraged thinking about social action. I provided consultation to the

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team regarding an audit I conducted on the formulation sessions we held. I gathered

information from other staff members during meetings and debriefs and engaged in

continuous risk assessment and management. In addition to having mentalising

conversations, CBT and systemic theories influence my conversations with the young

people. I used social inequalities formulations to guide my thinking and motivational

interviewing techniques to help promote a culture of change. I created and presented

information sheets on common mental health problems for the staff team and devised

training on motivational interviewing. I engaged in CPD relevant to the placement

and helped designed a qualitative piece of research on the employment scheme that

the project had been running.

Child and Adolescent Mental Health - Child and Adolescent Mental Health Service

(CAMHS)

I provided CBT, NT, systemic therapy, psychoeducation and social skills training to

children and adolescents aged between 6 and 15 years old and their families. I used a

range of standardised clinical measures and gathered information from clinical

records as well as from people in the child or adolescents professional and personal

networks. I used a range of standardised clinical measures and conducted three

neuropsychological assessments. I conducted observations in homes and schools and

consulted with schools regarding the outcome of individual therapy programmes. I

assessed for risk and made referrals to relevant agencies for issues of safeguarding. I

observed my supervisor conduct eye movement desensitisation and reprocessing. I

contributed to service development by jointly working with an educational support

worker to develop a leaflet for parents on the topic of school refusing. I provided CBT

supervision for a social worker and delivered a presentation at a team meeting.

169

Year I Assessments

PROGRAMME COMPONENT TITLE OF ASSIGNMENT

Fundamentals of Theory and Practice in Clinical Psychology (FTPCP)

Short report of WAIS-III data and practice administration

Research –SRRP

Practice case report Recovery model for a young man experiencing negative symptoms of psychosis

Problem Based Learning – Reflective Account

Reflections on problem based learning: The relationship to change

Research – Literature Review

Inference-based reasoning in obsessive-compulsiveness, delusions and schizotypy.

Adult – case report

Reflections-on-action: The use of Cognitive Behavioural Therapy with a single man in his late 30’s presenting with moderate to severe depressed mood, mild anxiety problems and unstable emotional personality traits; a notice therapists approach

Adult – case report

Cognitive Behavioural Therapy for anxiety and panic disorder with a man in his late 30’s with a diagnosis of schizo-affective disorder and a long term physical health condition that significantly impacted his presentation.

Research – Qualitative Research Project

What is the experience of low-intensity IAPT workers transitioning to clinical psychology training?

Research – Major Research Project Proposal

Inference-based reasoning in obsessive-compulsiveness, delusions and schizotypy.

170

Year II Assessments

PROGRAMME COMPONENT

TITLE OF ASSESSMENT

Research - SRRP

Research Research Methods and Statistics test

Professional Issues Essay

Successfully promoting psychological services to men, working class young people and cultural minorities present considerable challenges to clinical psychology, where the majority of practitioners are White European females”. To what extent can clinical psychology services reach out to these groups and what challenges does this pose for the profession?

Problem Based Learning – Reflective Account The Stride Family

People with Learning Disabilities/Child and Family/Older People – Case Report

Assignment Title: A Neurological assessment for dementia with a man in his mid sixties who presented with risk factors and significant concern.

Personal and Professional Learning Discussion Groups – Process Account

Personal and Professional Learning Discussion Group Process Account

People with Learning Disabilities/Child and Family/Older People – Oral Presentation of Clinical Activity

Working with Social Inequality, Difference and Diversity: Oral Case Presentation

171

Year III Assessments

PROGRAMME COMPONENT ASSESSMENT TITLE

Research - SRRPThe generic and specific supervisory competencies used by clinical psychologists in adult mental health services in a NHS Mental Health Trust

Research – MRP PortfolioThe relationship between inferential confusion, obsessive compulsiveness, schizotypy and dissociation in a non-clinical sample.

Personal and Professional Learning – Final Reflective Account

On becoming a clinical psychologist: A retrospective, developmental, reflective account of the experience of training

Child and Family/People with Learning Disabilities/ Older People/Specialist – Case Report

Observation, assessment and initial intervention with a primary school aged boy with selective mutism.

172

173