Rahe, Mahan and Rahe, Mahan and ArthurArthur

Today…Today… This morningThis morning

Aims and context of Rahe, recap of Aims and context of Rahe, recap of procedureprocedure

One on oneOne on one This afternoonThis afternoon

Timed essay on Rahe procedureTimed essay on Rahe procedure Peer assessmentPeer assessment Findings (if time)Findings (if time)

QuestionsQuestions What effect can stress have on our What effect can stress have on our

body?body?

Can stress make you ill?Can stress make you ill?

What did Selye find about stress?What did Selye find about stress?

ContextContext Psychosomatic:Psychosomatic:

A link between psychological state and A link between psychological state and physical healthphysical health

Relationship between stress and Relationship between stress and illnessillness Immune systemImmune system Cardiovascular system (heart and blood)Cardiovascular system (heart and blood)

ContextContext Thinking back to PY1, Thinking back to PY1,

what did what did Selye Selye find in his find in his research in his research research in his research on rats?on rats? Stress and illnessStress and illness

Holmes and HawkinsHolmes and Hawkins Not poverty itself which Not poverty itself which

causes TB, but the causes TB, but the emotional effects of poverty emotional effects of poverty

ContextContext Hawkins (1957)Hawkins (1957)

Compared TB patients to controls. Compared TB patients to controls. Matched for age, race etc.Matched for age, race etc.

Increase in “disturbing occurrences” in Increase in “disturbing occurrences” in the TB patients. the TB patients.

Is there a link between stressful Is there a link between stressful events and illness?events and illness?

ContextContext Issues with methodologyIssues with methodology

Research may lack…?Research may lack…?Dr Richard Rahe

There are biases inherent in using hospital samples and drawing conclusions from retrospective studies ... few attempts have been made to put the life stress and subsequent illness hypotheses in non hospital populations.

ContextContext Another issueAnother issue

All previous studies measure stress in different All previous studies measure stress in different ways. ways.

Social Readjustment Rating Scale (SRRS)Social Readjustment Rating Scale (SRRS) 43 critical life events based on 5000 case studies43 critical life events based on 5000 case studies All about life changes, both positive and negativeAll about life changes, both positive and negative Life change units (LCU) calculated by asking 400 Life change units (LCU) calculated by asking 400

people to rate them in terms of stresspeople to rate them in terms of stress

ContextContext Could we expose individuals to Could we expose individuals to

certain stressors, and measure their certain stressors, and measure their rate of illness? If not, why?rate of illness? If not, why?

Retrospective studies: issuesRetrospective studies: issues Recall from pastRecall from past Investigator effectsInvestigator effects Sample biasSample bias

AimsAims To overcome the methodological To overcome the methodological

issues of retrospective studies by issues of retrospective studies by carrying out a prospective study with carrying out a prospective study with more control. more control.

A normal population would be used A normal population would be used (sailors)(sailors)

Investigate the relationship between Investigate the relationship between stressful life events and future illness. stressful life events and future illness.

ProceduresProcedures Read the procedure on pg 81Read the procedure on pg 81

Fill in the blank information on the Fill in the blank information on the sheetsheet

FindingsFindings

What was the relationship between What was the relationship between Total Life Change Units (TLCU) Total Life Change Units (TLCU) and and illnessillness?? What was the correlation co-efficient for What was the correlation co-efficient for

the TCLUs six months before the cruise the TCLUs six months before the cruise and illness while on board?and illness while on board?

Relationship stronger for cruiser 1 and Relationship stronger for cruiser 1 and 3, and for married men3, and for married men

FindingsFindings Decile groupsDecile groups

All participants ranked in terms of their All participants ranked in terms of their TCLUs and put into one of ten bands, TCLUs and put into one of ten bands, each containing 10% of the total.each containing 10% of the total.

FindingsFindings Decile groups show a general trend, Decile groups show a general trend,

but it was an uneven distribution. but it was an uneven distribution. Groups banded into “High” and “low” Groups banded into “High” and “low”

illnessillness Plot this data into a bar chartPlot this data into a bar chart How clear is the relationship now?How clear is the relationship now?

Look at scatter graph on pg 82. Look at scatter graph on pg 82. Summarise these resultsSummarise these results

Findings and conclusionsFindings and conclusions More findingsMore findings

Read pg 91. What last piece of evidence is Read pg 91. What last piece of evidence is there?there?

ConclusionsConclusions What is the main conclusion?What is the main conclusion?

Read through the rest of the Read through the rest of the conclusions and highlightconclusions and highlight

Evaluating the Evaluating the methodologymethodology

Pg 84 has some good evaluation Pg 84 has some good evaluation points.points.

Using the pointers on the handout, Using the pointers on the handout, evaluate the studyevaluate the study

One evaluation point each, pass on. One evaluation point each, pass on.

Alternative EvidenceAlternative Evidence Rubin et al (1972)Rubin et al (1972)

Predictive relationship between SRE scores Predictive relationship between SRE scores and later illness in naval aviators in vietnamand later illness in naval aviators in vietnam

In other words, the higher the stress score, In other words, the higher the stress score, the more likely they were to be ill.the more likely they were to be ill.

What did Vidal (2006) What did Vidal (2006) and Gupta and Gupta and Gupta and Gupta (2004) Find?(2004) Find?

Alternative EvidenceAlternative Evidence Major life changes vs minor daily stressMajor life changes vs minor daily stress What minor stresses (hassles) can you What minor stresses (hassles) can you

think of?think of? See daily hassles sheetSee daily hassles sheet

DeLongis et al (1988)DeLongis et al (1988) +.59 correlation between daily hassles and +.59 correlation between daily hassles and

next day illnessnext day illness Two interpretations of this... Two interpretations of this...

Alternative EvidenceAlternative Evidence Rahe found a link between stress Rahe found a link between stress

and illnessand illness Descriptive rather than explanatoryDescriptive rather than explanatory

Kiecolt-Glaser et al (1984).Kiecolt-Glaser et al (1984). Blood tests taken before and during Blood tests taken before and during

the exam period. Levels of the exam period. Levels of natural natural killer cellskiller cells significantly lower significantly lower during the exam period. during the exam period.

Suggests that short term predictable Suggests that short term predictable stressors reduce immune system stressors reduce immune system functioning increasing illness.functioning increasing illness.

Alternative EvidenceAlternative Evidence Which piece of alterative evidence for Which piece of alterative evidence for

Langer and Rodin could be used here?Langer and Rodin could be used here?

Could stress be good?Could stress be good? Evans et al (1994)Evans et al (1994) sIgA levels increase for very short term stresssIgA levels increase for very short term stress

Use three colours to highlight research that Use three colours to highlight research that supportssupports, , contradicts,contradicts, or or developsdevelops Rahe’s Rahe’s research (some may be more than one research (some may be more than one colour). colour).