REVIEW

MPharm Year 4 Research Project

Medicine Management

Student name: Quang T. Bui

Student ID: 4548337

A systematic review of health literacy measurementsQuang Thanh.Bui., Bhattacharya Debi. PHD, Paul Duell.

AbstractOjective: Health literacy has been an important factor ever since it was first conceptualised. However, despite its application, there is no “gold standard” test for measuring health literacy. We conduct a systematic review of the currently available tools and examine the different domains that they measure. We also take a look at the practicality of these tools to use in a community pharmacy setting.

Methods: We searched Ovid, Medline, Embase, CINAHL and PHARMLINE (1946-2013) for studies using either validated tools or validating a newly developed tool. Data was extracted and quality was assessed using a combination of Cochrane, CASP and Cosmin for their psychometric data. Data was aggregated and reported as trend.

Key findings: Of the 49 eligible studies with unclear to poor quality, 15 validated a newly developed tool and 34 used validated tools. The newly developed tools did not show enough clinical data to make any recommendation. Limited evidences suggested that the difference between TOFHLA and REALM was not significant, but there was clear discrepancy between numeracy skill and health literacy level. There was an association between completion time of a test and health literacy level measured, however evidence was not enough to make a conclusion. We would recommend for NVS to be used primarily based on available data; however due to the poor quality of the studies included, more research needed to be done.

Conclusion: Despite the quality of the papers, our study showed a clear discrepancy between numeracy and health literacy score, and the similarity between TOFHLA and REALM. More research would be required before reaching to a conclusion, but our data suggest that NVS should be used in community pharmacy.

Keywords: systematic review, health literacy,

numeracy, community pharmacy.

Introduction

The concept of health literacy was first recognised

in 19741, even though the main focus at that time

was to educate children to be “literate” in health as

they were in other subject like science or maths.

Subsequently, earlier efforts to define this have

been limited to the individual’s ability to

understand basic reading to function in a health

care setting2. With the recent focus on patient

education and share decision making, the term

health literacy has become of increasing

importance; thus the concept has been broadened

out. Ratzan argued that health literacy was not

simply health knowledge, but also needed to take

into account on other factors like age, mental

capacity and environment3. All of these will

account for an individual’s ability to process the

information and actually take an appropriate

decision. Because of the complexity of these

elements, Ratzan recognised the difficulty of

coming to an agreement for a definitive description.

A recent definition by the World Health

Organisation further expanded the concept, with

the rationale that health literacy was not limited to

a measure of writing and reading, but more

importantly, what it allowed us to do. This included

both cognitive function and social skills that

created the necessary motivation for making an

informed health decision. The new included

elements were categorised by Nutbeam into three

levels of health literacy: functional (acquiring of

information), interactive (development of skill

under educational environment) and critical

(development of cognitive function and skills to

make analyses and informed decisions) 4. A recent

definition has broadened the term

to include a group of individuals with regards to

public health literacy5.

The vast amount of definitions being used in

practice has led to a problem when considering a

measurement tool to be “standard”. A logic model,

developed by Berkman et al to analyse health

literacy, covers all three elements of the Nutbeam

definition; along with a simplistic behaviour model

called the Integrative Theory6..

The model took into account the common

influencing factors that could affect an individual’s

health literacy level, such as age, gender, ethnicity

and the relationship between the patient and

physician. A low level of health literacy could

affect an individual’s ability to access information

and evaluate emergency situation relating to him or

another’s health. This ability, coupled with

personal resources and the right level of support,

could define one’s health behaviour and his

adherence and lead to better outcomes: prevention

of diseases, lowering of risk factors, etc. Hence,

incorporating the same factors into a health literacy

measurement could potentially improve its level of

accuracy. His model, however, is not the definitive

guide to developing a measurement tool. The

direction of good outcome is not specified all the

time: while increase in adherence will lead to good

outcome, an increase in hospitalisation, however,

leads to bad outcome. Furthermore, several factors

are not included in this model. Higher cognitive

functions such as processing speed, inductive

reasoning or verbal ability have been shown to

impact an individual’s health literacy skill7.

Personal motivation, the extent to which an

individual actively seek out and engage with

information, also play an important part in defining

health literacy skill. A lack of motivation could

become a barrier and thus prevent the patient from

accepting diagnosis and reduce therapy

compliance8. A good tool therefore should cover all

these areas and be able to convert them to a rational

and meaningful scale.

Multiple tools are currently being used in practice

such as TOFHLA (Test of Functional Health

Literacy in Adult) or REALM (Rapid Estimate of

Adult Literacy in Medicine); each with separate

questions sets and covers different areas of the

definition. While various forms of TOFHLA

measures patient’s ability to perform health-related

task requiring reading and computational skills9,

REALM focuses on recognition and pronunciation

of medical words10. Similarly to TOFHLA, the

NVS (Newest Vital Sign) screening tool measures

the patient’s reading comprehension and basic

problem solving skills11. Most of these tools

focused on communicative or basic comprehension

elements and cover the static definitions of health

literacy, i.e. an individual’s progression in health

literacy over time is not reported. Each tool

measures different domains that affected an

individual’s health literacy level, as well as

covering different elements of Nutbeam’s

definition. To complicate the matter further, each

test also has a number of variations; S-TOHFLA

for example is a shorter version of TOHFLA and

can be used either with or without a time limit. This

small change can potentially produce significantly

different results when using correctly. Additionally,

the fact that these current tools only focus on

measuring an individual’s functional health literacy

skill raises the question of whether it is actually

useful to measure the other domains of Nutbeam’s

definition.

Because of these complications, despite their

frequent use, there has not been many reviews

conducted for comparison between these tools, and

most studies were done at a small scale. Either of

these tools is considered “standard” because of

their difference and applications. Therefore, further

research is required to evaluate the sensitivity and

validity of the current tools in use.

In this paper, we conduct a narrative review of the

current measurement tools, following Nutbeam’s

definition on the three elements of health literacy.

Thus, our focus was on determining the feasibility

of using the existing tools in a healthcare setting.

The sensitivity, validity and acceptability of each

tool will be taken into consideration when applying

to the healthcare environment. As each tool covers

different domains of the definition, a clear

description of domains representation by existing

tools will be reported. Furthermore, an assessment

on how each domain affect the final outcome of

health literacy will be conducted.

Methods

A standard systematic review method using the

Cochrane Guidance12 and York Handbook13 was

performed by two independent researchers in

autumn 2012 and spring 2013 and the results

compared and combined to obtain information

regarding the objectives outlined above.

Studies were identified through electronic searches

through the database of Ovid, Medline, Embase,

CINAHL and PHARMLINE (1946-2013). Search

strategies identified appropriate subject headings

plus text words: 19 keywords “measure”, “tool”,

“assess”, “critical”, “functional”, “communicate”,

“motivation”, “cognitive”, “Social skill”,

“numeracy”, “acceptable”, “feasible”, “valid”,

“perform”, “psychometric”, “score”, “sensitive”,

“specific” and “reliable” were combined (without

quotes) using truncations (*), wild cards ($),

hyphens and other relevant Boolean operators

and/or were combined with the search terms health

literacy or health competen*. From the resulting

list, studies were selected based on their titles and

abstracts.

Studies were included if they were 1) conducted in

a healthcare setting, with participants old enough to

have gone to school to be taught to read, 2)

measuring at least one of the domains of health

literacy defined by Nutbeam: functional,

communicative or critical, 3) along with studies

considering numeracy from a health literacy

perspective, and 4) including descriptive or

psychometric data comparing validated tools with

new tools. Exclusion criteria included studies

which only validated a foreign version of an

existing health measure developed in an English

speaking country, were conference abstracts or had

a sample size less than 50 participants.

An abstract screening tool was developed based on

the study inclusion and exclusion criteria to

identify the articles to be included in the systematic

review. Screening process was undertaken by two

independent researcher. Disagreements were

resolved by consensus and recorded for study

purpose.

Independent, duplicate data extraction of each

included study was performed by two researchers.

The data extraction form developed for this study

was piloted using a sample of studies and checked

for inter-rater reliability for the recording of

outcome data and quality assessment. Differences

were resolved through discussion or third party

referral if required. The following data was

extracted from the full papers:

Details of the authors, country of

publication/study, year of publication,

study population, setting and recruitment,

number of patients invited to the study,

number of patients that signed up and

participant dropout rates, exclusion

criteria. Demographic data such as sex and

age.

Details of the health literacy measure(s)

including the number and type of

questions asked, the scoring system, time

taken to complete and the different

classifications of health literacy within the

measurement scale and the domain

measured and results obtained.

Psychometric outcome data measures such

as content, criterion construct and face

validity, specificity, feasibility, sensitivity

and acceptability.

Independent, duplicate quality assessment was

conducted as part of the study by two researchers.

The main tool was decided to be the Cochrane

tool12 for reporting bias because of its reputation as

a validated tool. Although the “Sequence

generation” criterion was removed for not fitting

with the study, it was felt that this was a best fit for

the study. Additional assessment criterion was

included from the CASP co-hort study

questionnaire14. Studies measuring psychometric

data would be assessed by the Cosmin checklist15

for internal consistency, content validity and

criterion validity.

Results

Abstract screening

Based on the combination of keywords and search

terms, 453 publications were identified. From this

pool of samples, abstract screening process was

conducted independently and the final result, after

discussion, was 79 publications selected to data

extraction process. The agreement rate between

two researchers was high (93%), and the strength

of the agreement was good (Kappa= 0.799, SE =

0.035).

Figure 1:Flow diagram for selection of studies.

Data extraction

Out of the 79 publications selected, 18 were

excluded for being conference abstract, 6 as full

paper unavailable, 3 as translated version of an

English health literacy tool, 2 as fewer than 50

patients sample size, and 1 for being written in

another language. The final number of articles

chosen was 49 (62.0%) out of 79. Of the 49

articles, 15 (30.6%) were validation of a newly

Iden

tifica

tion Records identified through

database searching (n = 453)

Record screened (n=453)

Record excluded (n= 374)

Scre

enin

g

Full text article accessed (n=79)

Full text article excluded (n= 30)

Conference abstract n=18

Full text unavailable n=6

Translated version of an English health literacy tool n=4Studies included in

systematic review (n=49)In

clud

ed

developed tool. Figure 1 showed the flow diagram

of the studies selection process.

Analysis of study and methods

Over three quarters (79.1%) of the studies were

collected from convenient sample. The majority

(78.9%) of studies were conducted in the USA and

performed in English (82.7%). The target

population of most studies were mostly white,

African American, Latinos or Hispanic patients.

The sample size ranged from 50 to 6,819. Table 1

showed a summary of the studies involved in this

review, including participation rate and

demographic data.

Main exclusion criteria of most studies were visual

impairment (35.4%), cognitive impairment (18.8%)

and hearing impairment (14.6%).

Table 1: Summary of the studies included

Year of

publishi

ng

Authors Research Objectives (Approached/

Eligible)

Drop out

during

assessment

Time

required

Mean

age

Male

percentag

e

Female

percenta

ge

2011 Kirk K.J. et.al Performance of health literacy tests among older adults

with diabetes16

(563/593) 128 NA NA 38.1 61.8

2011 Kim M.T. et.al Development and validation of the high blood

pressure-focused health

literacy scale17

(440/NA) NA 10-15

minutes

70.9 30.5 69.5

2012 Ghaddar S.F.

et.al

Adolescent health literacy: The importance of credible

sources for online health information18

(305/NA) 25 NA 15.9 40.2 59.8

2011 Yin H.S. et.al Assessment of health literacy and numeracy among

Spanish-speaking parents of young children: Validation

of the Spanish parental health literacy activities test

(PHLAT Spanish)19

184/263) 8 NA 27.7 10.8 89.2

2011 Ferguson B.

et.al

Assessing literacy in clinical and community settings:

the patient perspective20

(150/NA) NA 40-45

minutes

NA 22 78

2011 Patel P.J. et.al Testing the utility of the newest vital sign (NVS) health

literacy assessment tool in older African - American

patients21

(62/NA) NA 17 minutes 73.2 NA NA

2011 McNaughton

C. et.al

Short, subjective measures of numeracy and general

health literacy in an adult emergency department22

(209/NA) 2 NA NA 55 45

2011 White III R.O.

et.al

Development and validation of a spanish diabetes-

specific numeracy measure: DNT-15 latino23

(150/163) 6 NA 47.8 38 62

2011 Robinson S. Assessing health literacy in heart failure patients24 (609/612) 3 7 66 58.8 41.2

et.al minutes/N

TL

2010 Golbeck A.

et.al

Correlating reading comprehension and health

numeracy among adults with low literacy25

(144/NA) NA NA NA 42 58

2010 Sakar U. et.al Validation of self-reported health literacy questions

among diverse english and spanish -speaking

populations26

(296/NA) NA NA 54.9 42.6 57.4

2010 Wu A.D. et.al Developing and evaluating a relevant and feasible

instrument for measuring health literacy of Canadian

high school students27

(275/NA) NA NA NA 48 52

2010 Clayman M.L.

et.al

Ask, understand, remember: a brief measure of patinet

communication self-efficacy within clinical

encounters28

(330/NA) NA NA 53.58 32.1 67.9

2009 Ozdemir H.

et.al

Health literacy among adults: a study from Turkey29 (456/579) NA NA 36.2 39.5 60.5

2009 Macek M.D.

et.al

Measuring conceptual health knowledge in the context

of oral health literacy: Preliminary results30

(100/NA) NA NA NA 45 55

2010 Kumar D. et.al Parental understanding of infant health information:

Health literacy, numeracy and the Parental Health

Literacy Activities Test PHLAT)31

(261/413) NA 21 minutes 25.6 11 89

2010 Lee.S-Y.D.

et.al

Short assement of health literacy- Spanish and English:

A comparable test of health literacy for spanish and

english speakers32

(403/NA) NA NA NA 44 56

2009 Rawson K.A.

et.al

The METER: A brief, self-administered measure of

health literacy33

(153/NA) NA 2 minutes 62.7 76.5 23.5

2009 Sabbahi D.A. Development and evaluation of an oral health literacy (100/NA) NA NA 39 27 73

et.al instrument for adults34

2009 Oettinger

M.D. et.al

Color-Coding improves parental understanding of body

mass index charting35

(165/285) 2 NA NA NA NA

2009 Lee T.W. et.al Testing health literacy skills in older Korean adults36 (410/NA) 11 20.1

minutes

73.3 39 61

2008 Ishikawa H.

et.al

Measuring functional, communicative, and critical

health literacy among diabetic patients37

(157/169) 19 NA 65 52.9 47.1

2008 Ishikawa H.

et.al

Developing a measure of communicative and critical

health literacy: A pilot study of Japanese office

workers38.

(229/419) 39 NA 43.2 100 0

2007 Gong D.A.

et.al

Development and testing of the test of functional health

literacy in dentistry (TOFHLiD)39

(102/NA) NA NA NA 12 88

2007 Lee J.Y. et.al Development of a word recognition instrument to test

health literacy in dentistry: the REALD-30 - a brief

communication40

(202/NA) NA NA 44.7 43.6 56.4

2007 Wagner C.

et.al

Functional health literacy and health-promoting

behaviour in a national sample of British adults41

(759/NA) 40 NA 47.2 42 58

2007 Donelle L.

et.al

Assessing health numeracy among community-

dwelling older adults42

(140/NA) NA 90 minutes NA 26.4 73.6

2007 Chisolm D.J.

et.al

Measuring Adolescent Functional Health Literacy: A

pilot validation of the Test of Functional Health

Literacy in Adults43

(50/NA) NA 45 minutes

total,

TOFHLA

12.9

minutes

14.7 48 52

2007 Baron-Epel O. Validation of a Hebrew health literacy test44 (119/138) NA NA NA 47.9 52.1

et.al

2006 Apter A.J.

et.al

Asthma numeracy skill and health literacy45 (73/NA) NA NA 47 15.1 84.9

2006 Lee S.Y. et.al Development of an easy-to-use Spanish health literacy

test46

(403/NA) NA NA 34.2 for

Spanish,

43.7 for

English

44 56

2006 Zun L.S. et.al English-language competency of self-declared English-

speaking Hispanic patients using written tests of health

literacy47

(105/354) NA NA NA 37.1 62.9

2005 Weiss B.D.

et.al

Quick assessment of literacy in primary care: The

newest vital sign48

(500/625) NA NA 41.3 for

English,

40.8 for

Spanish

NA NA

2005 Aguirre A.C.

et.al

Perfomance of the English and Spanish S-TOFHLA

among publicly insured Medicaid and Medicare

patients49

(2370/NA) NA NA Hispanic

English

31.7

13 87

            Hispanic

Spanish

42.7

22 78

            English

44.9

25 75

2004 Sanders L.M.

et.al

Number of children's books in the home: An indicator

of parent health literacy50

(163/NA) NA NA NA NA NA

1998 Baker D.W. Development of a brief test to measure functional (248/283) 7 NA 44 47 53

et.al health literacy51

2012 Apolinario D.

et.al

Short Assessment of Health Literacy for Portuguese-

speaking adults52

(226/360) NA NA 74.4 28.9 71.1

2011 Pendlimari R.

et.al

Assessment of Colon Cancer Literacy in screening

colonoscopy patients: a validation study53

(63/NA) 2 NA 64 46 54

2007 Diamond J.J.

et.al.

Development of a reliable and construct valid measure

of nutritional literacy in adults54

(341/NA) NA NA 46.4 22 78

2011 Fransen M.P

et.al.

Applicability of international available health literacy

measures in the Netherlands55

(289/NA) NA NA 59.7 66 34

2009 Huizinga

M.M. et.al.

Literacy,numeracy and portion-size estimation skills56 (169/248) 5 45 minutes 45.8 29 71

2009 Kathleen J.

et.al.

Billingual health literacy assessment using the Talking

Touchscreen/la pantalla parlanchina: Development and

pilot testing57

(231/NA) NA NA NA English 35,

Spanish

25.4)

English

65,

Spanish

74.6)

2011 Tsai T.I. et.al Methodology and validation of health literacy scale

development in Taiwan58

           

2009 Miller M.J.

et.al

Application of the cloze procedure to evaluate the

comprehension and demonstrate rewriting of pharmacy

educational materials59

 (154/162)  1  NA  NA  28.6 71.4

2010 Ohl M. et.al Do brief screening questions or provider perception

accurately identify persons with low health literacy in

the HIV primary care setting?60

 (147/149) 2 NA NA 71 29

2008 Cavanaugh K.

et.al

Association of numeracy and diabetes control61  (398/615)  NA NA NA 49 51

2010 Galesic M. Graph literacy: A cross-cultural comparison62 (987/NA)  NA NA NA Germany Germany

et.al 50.3, US

48.4

49.7, US

51.6

2009 Jeppesen K.M.

et.al

Screnning questions to predicts limited health literacy:

A cross-sectional study of Patients with diabetes

mellitus63

 (225/396) NA NA NA NA NA

2008 Hanchate A.D.

et.al

The demographic assessment for health literacy

(DAHL): A new tool for estimating association

between health literacy and outcomes in national

surverys64

 Prudential Study

(2,824/NA)

NHIS-Elderly

Study (6,819/NA)

NA NA NA Prudential

Study 42,

NHIS-

Elderly

Study 38

Prudentia

l Study

58,

Elderly

Study 62

Testing instruments

Several instruments were used in these studies to

measure the three aforementioned domains of

Nutbeam’s definition of health literacy. Of the 25

known assessment tools used, 7 were used in more

than 1 study and were consisted of variation of

TOFHLA, REALM, NVS and WRAT numeracy

tests. Many studies aimed to validate a new

assessment tool, thus clinical data was limited.

The most commonly used health literacy measure

tools were S-TOFHLA (50%), REALM (32.5%)

and NVS (20%). The numeracy aspect of the

TOFHLA and its variance was often compared to

the WRAT numeracy test result.

The majority of the tests only measured functional

health literacy (82.5%), i.e. the subject’s ability to

acquire and process information. This included

both validated tests and newly developed tools for

validation. In 48 studies, only 1 attempted to

measure all 3 domains of Nutbeam’s definition of

health literacy37.

Data analysis

Out of 48 studies, only 8 (16.7%) measured both

variation of TOFHLA and REALM; all pointed to a

similarity in result and detection of inadequate

health literacy between the two tests. Correlation

between these tests was suggested to be

positive43,51, indicating that they both measured the

same functional domain of the patient’s health

literacy. Additionally, study by Ferguson20 claimed

that patients have no real preference between

TOFHLA and REALM.

There was little evidence comparing the result of

NVS and TOFHLA or REALM. One study by

Kirk16 compared the three tools reported a higher

detection of inadequate health literacy from NVS

than TOFHLA (49.8% compared to 28.8%).

However, Patel reported no real differences in

score between NVS and TOFHLA21. Thus, there

was no conclusive argument to be made for the

differences between NVS and TOFHLA/REALM.

Translated versions of NVS and REALM 29,55, on

the other hand, showed a clear discrepancy between

the score of these two instruments: with a

difference in inadequate literacy estimation of 30%

in both cases (higher estimation with REALM in

Turkish version and NVS in Dutch version).

8 studies in total (16.7%) employed a version of the

Wide Range Achievement Test (WRAT) or Cloze

to measure numeracy aspect of the patients along

with a health literacy assessment. In all 6 studies,

there were a clear discrepancy between a subject’s

health literacy skill and numeracy skill: the

majority of subjects displayed poor numeracy skill

(over 50% in all cases) despite a high level of

literacy skill. Miller estimated that only 8% of

patients recording poor numeracy score (Cloze in

this case) actually be tested positive for

marginal/inadequate health literacy by S-

TOFHLA59. Additionally, a study by Golbeck

suggested that only 60% of patients had the same

level of reading and numeracy (inadequate,

marginal or adequate), and 20% of patients were

reported to have one skill at a higher level than the

other25.

From 15 of the newly developed tools, 10 (66.7%)

were developed based on a current tool and

reported to have good validity and correlation with

either TOFHLA or REALM. However, each tool

was only used in one study, hence further research

would be required before they could be applied.

Completion rate and acceptability of the assessment

was reported each by 1 study, thus no conclusion

could be drawn. The time required to complete the

tests ranged from 2 to 90 minutes from 9 studies

(18.8%); as many employed multiple tests and only

total completion time was reported.

Quality assessment

The overall quality of articles included in this

review was poor, with all 48 studies assessed as

either of unclear or poor quality by our quality

assessment tool. The most reported flaws of the

studies were too few recruitment sites, missing

drop-out rate of the subjects and the employment of

multiple tests for elderly patients.

Discussion

The results of this review suggested that there was

no clear difference between the currently used tests

to determine a patient’s health literacy level. The

evidences were consistent between TOFHLA and

REALM; however data for comparison of such

tests with the NVS was limited and more research

would be required before any conclusion could be

drawn. Additionally, early evidences suggested a

high acceptability and no clear preference between

TOFHLA and REALM from patient, it could be

stated that the choice for community pharmacy

would come down to preference, time constraint

and the availability of the tests.

Conversely, the clear discrepancy in results

between numeracy and health literacy score

showed that while these tests all measured the same

functional domain of Nutbeam’s definition, the

extent to which each factors affected the outcome

was not the same. More research would be required

to determine whether numeracy tests should be

included: few studies had suggested that numeracy

skills also had an impact on the patient’s health 45,

65, although no firm conclusion could be drawn 6.

Different to the systematic review of Berkman6 and

Sorensen66, our study focused on the assessment

tools used to determine a patient’s health literacy

skill and their applicability to use in a community

health setting.

This study shares many limitations from other

systematic reviews. Although we conducted an

extensive literature search, the search was limited

to online journals only and evidently not all

published data had been included. Unpublished

studies and reports (‘grey literature’) were not

sought out.

Although we did not employ a standard data

extraction tool for this study, the process was

performed by two independent researchers and any

disagreements discussed until consensus was

reached. We were limited to the amount of

information included in the studies. Very few

studies reported patients' completion rate or reason

for patient drop-out; while this could be an

important factor to determine a potential flaw of the

instruments, no conclusion was drawn.

Additionally, the quality assessment tool was also

developed for the purpose of this review and

performed by two independent researchers.

Although every single aspect of the quality of each

paper was discussed, a general consensus was

formed between two researchers about the quality

of each study.

Another limitation that was unique to this review

was the overall quality of the included studies.

Most studies recruited patients as convenient

sample and from a few locations varying in settings

with little to no reason given for such choice of

location, thus negatively affecting their

generalisability. Some studies required the patients

to take multiple tests which could last up to 90

minutes42 and thus could lead to an increase in

drop-out rate.

Possible reason for the demographic of mostly

female, age 18-50 of the review was due to the

recruitment method of many studies: a convenient

sample pool recruited from health clinics. This

could be argued as a representative data of a

general health setting; however as no study so far

had explored the general population of a

community pharmacy, further research was

recommended.

The Test of Functional Health Literacy in Adult

(TOFHLA) and Rapid Estimate of Adult Literacy

in Medicine (REALM) were the most commonly

used and compared in this review. Both tests

measured a patient’s functional health literacy

level9.10, as suggested by their similarity in

detection rate. The Newest Vital Sign (NVS) tool,

however, showed mixed results from both

TOFHLA and REALM. This could be an

indication that the domains of health literacy

measured by NVS might be different from the

others. In the NVS test, patients were given

information about the nutritional value of a pint of

ice cream and asked a series of 6 questions in the

style of Yes/No48. The main difference between

NVS and the other two tests was that during the

testing period, the patient had access to that

information and was allowed to consult them as

they wished. This subsequently meant that instead

of having to remember the information, the main

focus of the test was how well the patient could

interpret the data and extract information from the

given fact. Thus, it could be suggested that NVS

measured not only the functional, but also the

communicative domain of health literacy; however

more evidence was required before any conclusive

comment could be drawn.

The contribution of each domain (functional,

communicative and critical) to an individual’s

overall health literacy level was not discussed so

often. In a study by Ishikawa et. al.37, a new scale

was developed to measure all three domains of the

patient’s health literacy. The study showed a

positive association between communicative and

critical health literacy, suggesting that both

domains involved more advanced skills than

functional health literacy. This was further

reinforced by the correlation between the number

of information sources consulted with

communicative and critical health literacy and not

functional health literacy, indicating that the

current tool might be sufficient to measure an

individual’s basic health literacy level in the

community pharmacies.

Miller59 showed a positive correlation between the

Cloze procedure and S-TOFHLA (which contained

a numeracy section modified from Cloze9).

However, he argued that the stronger correlation

between S-TOFHLA and REALM suggested that

both tests emphasized word recognition over actual

content comprehension. This suggestion was

further reinforced by the discrepancy between their

scores and WRAT score, specifically its numeracy

aspect. Additionally, a study by Golbeck25 showed

only 60% correlation between an individual’s level

of reading and numeracy skill using the current

tests. Although not enough research had been put

into studying the relationship between numeracy

skills and health literacy level, there had been

evidence in specific cases 45,48and we suggested that

a health literacy test including numeracy, such as

NVS should be preferred than other word

recognition tests.

The aspect of completion time was not recorded by

most studies; however an association between time

and health literacy score had been shown in a study

by Robinson24. Comparing between a standard 7

minutes S-TOFHLA test and a no-time-limit (NTL)

S-TOFHLA showed that on average, patients

attempted more questions, and an overall increase

in average score of 15 %. The study suggested that

the 7 minutes limit of S-TOFHLA might

underestimate the literacy level of patients;

however not enough evidence could be gathered to

make a conclusion. Thus, until more researches

were done, the practicality of carrying out health

literacy test in a community pharmacy required a

tool that was quick to use. Between the most

commonly used tools, NVS was shown to be the

quickest tool to used with only 6 questions and an

average completion of 2.9 minutes 48. Additionally,

some studies had pointed out the flaw of REALM

(tendency to both overestimate and underestimate

in the mid-range section) 51 and TOFHLA (many

items with weak correct alternatives, leading to an

easier answer choice for patient) 57. Therefore, we

suggested that based on the available evidences, the

NVS test should be used in the community

pharmacy setting until a better tool that measured

the three domains was developed. We also

suggested future studies to include the aspect of

completion time to further understand this issue.

Conclusion

The available evidences on health literacy

measurement tools did not allow us to draw any

definitive conclusion. However, current data

suggested that the difference between TOFHLA

and REALM was minimal and there was a clear

disparity between these tools and the numeracy

score of an individual. Despite the fact that there

was an association between completion time and

the health literacy score, not enough evidence was

given to assess its effect. Thus, until a better tool

measuring all three domains of health literacy was

developed, we suggested that NVS should be used

based on its short completion time and the

inclusion of a numeracy aspect.

However, because of the quality of the data, many

of these studies were not reproducible and further

research would be required before any conclusive

comment could be made.

References

1.Simonds SK(1974): Health education as

social policy.Health Education

Monograph, 2 :1-25. 

2.American Medical Association (1999) Ad

Hoc Committee on Health Literacy for the

Council on Scientific Affairs: Health Literacy:

Report of the Council on Scientific Affairs.

Journal of the American Health

Association: 281, 552–557.

3.Ratzan SC (2001): Health literacy:

communication for the public good: 212.

4.Nutbeam D (2000): Health literacy as a public

health goal: a challenge for contemporary

health education and communication strategies

into the 21st century. What is health literacy? :

263,264.

5.Freedman DA, Bess KD, Tucker HA, Boyd

DL, Tuchman AM, Wallston KA (2009). Public

Health Literacy Defined. American Journal of

Preventive Medicine. 36(5), 446-51.

6.Berkman ND, Sheridan SL, Donahue KE et al

(2011). Health Literacy Interventions and

Outcomes: An Updated Systematic Review.

Evidence Report/Technology Assessment

Number 199 , ES 2-3.

7.Wolf MS, Curtis LM, Wilson EA et al (2012).

Literacy, cognitive function and health: results

of the LitCog study. Journal of General

Internal Medicine: 27, 1300-7.

8.Edwards M, Wood F, Davies M, Edwards A

(2012). The development of health literacy in

patients with a long-term health condition: the

health literacy pathway model. BMC Public

Health, 12:130.

9.Parker RM, Baker DW, Williams MV, Nurss

JR (1995).The test of functional health literacy

in adults. Journal of Internal General Medicine.

10, 537-541.

10.Ibrahim SY, Reid F, Shaw A et al (2008).

Validation of a health literacy screening tool

(REALM) in a UK population with coronary

heart disease. Journal of Public Health.30, 449-

455.

11. Osborn CY, Weiss BD, Davis TC et al

(2007).Measuring Adult Literacy in Health

Care: Performance of the Newest Vital Sign.

American Journal of Health Behaviour. 31,

S36-S46.

12. Higgins JPT, Green S, editors. Cochrane

Handbook for Systematic Reviews of

Interventions 4.2.6 [updated September 2006].

In: The Cochrane Library, Issue 4, 2006.

Chichester, UK: John Wiley & Sons, Ltd

13. Centre for Reviews and Dissemination.

Systematic Reviews. CRD’s guidance for

undertaking reviews in health care. University

of York: 2009.

14. CRITICAL APPRAISAL SKILLS

PROGRAMME: Making sense of evidence

about clinical effectiveness. CASP UK [online]

2012.

http://www.casp-uk.net/wp-content/uploads/201

1/11/CASP_Cohort_Appraisal_Checklist_14oct

10.pdf (accessed 14th Octoober 2012).

15. Terwee C.B. Cosmin checklist with 4-point

scale. COSMIN [online]. 2011.

http://www.cosmin.nl/images/upload/File/COS

MIN%20checklist%20with%204-point

%20scale%2022%20juni%202011.pdf

(accessed 22nd June 2011).

16. Kirk K.J. et.al (2011). Performance of

health literacy tests among older adults with

diabetes. J Gen Intern Med. 27(5), 534-40.

17. Kim M.T. et.al (2011). Development and

validation of the high blood pressure-

focused health literacy scale. Patient Educ

Couns. 87(2), 165-70.

18. Ghaddar S.F. et.al (2012). Adolescent health

literacy: The importance of credible sources for

online health information. J Sch Health. 82(1),

28-36.

19. Yin H.S. et.al (2012). Assessment of health

literacy and numeracy among Spanish-speaking

parents of young children: Validation of the

Spanish parental health literacy activities test

(PHLAT Spanish). Acad Pediatr. 12(1), 68-74.

20. Ferguson B. et.al (2011). Assessing literacy

in clinical and community settings: the patient

perspective. J Health Commun. 16(2), 124-34.

21. Patel P.J et.al (2011). Testing the utility of

the newest vital sign (NVS) health literacy

assessment tool in older African - American

patients. Patient Educ Couns. 85(3), 505-7.

22. McNaughton C. et.al (2011). Short,

subjective measures of numeracy and general

health literacy in an adult emergency

department. Acad Emerg Med. 18(11), 1148-55.

23.White III R.O. et.al (2011). Development

and validation of a spanish diabetes-specific

numeracy measure: DNT-15 latino. Diabetes

Techno Ther. 13(9), 893-8.

24. Robinson S. et.al (2011). Assessing health

literacy in heart failure patients. J Card Fail.

17(11), 887-92.

25.Golbeck A. et.al (2011). Correlating reading

comprehension and health numeracy among

adults with low literacy. Patient Educ Couns.

84(1), 132-4.

26. Sakar U. et.al (2010). Validation of self-

reported health literacy questions among

diverse english and spanish -speaking

populations. J Gen Intern Med. 26(3), 265-71.

27. Wu A.D. et.al (2010). Developing and

evaluating a relevant and feasible instrument for

measuring health literacy of Canadian high

school students. Health Promot Int. 25(4), 444-

52.

28. Clayman M.L. et.al (2010). Ask,

understand, remember: a brief measure of

patient communication self-efficacy within

clinical encounters. J Health Commun. 15(2),

72-9.

29. Ozdemir H. et.al (2010). Health literacy

among adults: a study from Turkey. Health

Educ. Res. 25(3), 464-77.

30.Macek M.D. et.al (2010). Measuring

conceptual health knowledge in the context of

oral health literacy: Preliminary results. J

Public Health Dent. 70(3), 197-204.

31. Kumar D. et.al (2010). Parental

understanding of infant health information:

Health literacy, numeracy and the Parental

Health Literacy Activities Test PHLAT). Acad

Pediatr. 10(5), 309-16.

32. Lee S.Y. et.al (2010). Short assement of

health literacy- Spanish and English: A

comparable test of health literacy for spanish

and english speakers. Health Serv Res. 45(4),

1105-20.

33. Rawson K.A. et.al (2010). The METER: A

brief, self-administered measure of health

literacy. J Gen Intern Med. 25(1), 67-71.

34. Sabbahi D.A. et.al (2009). Development and

evaluation of an oral health literacy instrument

for adults. Community Dent Oral Epidemiol. 37

(5), 451-62.

35.Oettinger M.D. et.al (2009). Color-Coding

improves parental understanding of body mass

index charting. Acad Pediatr. 9(5), 330-8.

36. Lee T.W. et.al (2009). Testing health

literacy skills in older Korean adults. Patient

Educ Couns. 75(3), 302-7.

37. Ishikawa H. et.al (2008). Measuring

functional, communicative, and critical health

literacy among diabetic patients. Diabetes Care.

31(5), 874-9.

38. Ishikawa H. et.al (2008). Developing a

measure of communicative and critical health

literacy: A pilot study of Japanese office

workers. Health Promot Int. 23(3), 269-74.

39. Gong D.A. et.al (2007). Development and

testing of the test of functional health literacy in

dentistry (TOFHLiD). J Public Health Dent.

67(2), 105-12.

40. Lee J.Y. et.al (2007). Development of a

word recognition instrument to test health

literacy in dentistry: the REALD-30 - a brief

communication. J Public Dent Health. 67(2),

94-8.

41. Wagner C. et.al (2007). Functional health

literacy and health-promoting behaviour in a

national sample of British adults. J Epidemiol

Community Health. 61(12), 1086-90.

42. Donelle L. et.al (2007). Assessing health

numeracy among community-dwelling older

adults.J Health Commun.12(7), 651-65.

43. Chisolm D.J. et.al (2007). Measuring

Adolescent Functional Health Literacy: A pilot

validation of the Test of Functional Health

Literacy in Adults. J Adolesc Health. 41(3),

312-4.

44. Baron-Epel O. et.al (2007). Validation of a

Hebrew health literacy test. Patient Educ

Couns. 67(1-2), 235-9.

45. Apter A.J. et.al (2006). Asthma numeracy

skill and health literacy. J Asthma. 43(9), 705-

10.

46. Lee S.Y. et.al (2006). Development of an

easy-to-use Spanish health literacy test. Health

Serv Res. 41(4 Pt 1), 1392-412.

47. Zun L.S. et.al (2006). English-language

competency of self-declared English-speaking

Hispanic patients using written tests of health

literacy. J Natl Med Assoc. 98(6), 912-917.

48. Weiss B.D. et.al (2005). Quick assessment

of literacy in primary care: The newest vital

sign. Ann Fam Med. 3(6), 514-22.

49. Aguirre A.C. et.al (2005). Perfomance of

the English and Spanish S-TOFHLA among

publicly insured Medicaid and Medicare

patients. Patient Educ Couns. 56(3), 332-9.

50. Sanders L.M. et.al (2004). Number of

children's books in the home: An indicator of

parent health literacy. Armbul Pediatr. 4(5),

424-8.

51. Baker D.W. et.al (1999). Development of a

brief test to measure functional health literacy.

Patient Educ Couns. 38(1), 33-42.

52.Apolinario D. et.al (2012). Short Assessment

of Health Literacy for Portuguese-speaking

adults. Rev Saude Publica. 46(4), 702-11.

53. Pendlimari R. et.al (2012). Assessment of

Colon Cancer Literacy in screening

colonoscopy patients: a validation study. J Surg

Res. 175(2), 221-6.

54. Diamond J.J. et.al (2007). Development of a

reliable and construct valid measure of

nutritional literacy in adults. Nutritional

Journal. 6,5.

55. Fransen M.P. et.al (2011). Applicability of

international available health literacy measures

in the Netherlands. J Health Commun. 16(3),

134-49.

56. Huizinga M.M. et.al (2009).

Literacy,numeracy and portion-size estimation

skills. Am J Prev Med. 36(4), 324-8.

57. Kathleen J.Y. et.al (2009). Billingual health

literacy assessment using the Talking

Touchscreen/la pantalla parlanchina:

Development and pilot testing. Patient Educ

Couns. 75(3), 295-301.

58. Tsai T.I. et.al (2011). Methodology and

validation of health literacy scale development

in Taiwan. J Health Commun. 16(1). 50-61.

59. Miller M.J. et.al (2009). Application of the

cloze procedure to evaluate the comprehension

and demonstrate rewriting of pharmacy

educational materials. Ann Pharmcother. 43(4),

650-7.

60. Ohl M. et.al (2010). Do brief screening

questions or provider perception accurately

identify persons with low health literacy in the

HIV primary care setting? AIDS Patient Care

STDS. 24(10), 623-9.

61. Cavanaugh K. et.al (2008). Association of

numeracy and diabetes control. Ann Intern Med.

148(10), 737-46.

62. Galesic M., Garcia-Retamero R. (2010).

Graph literacy: A cross-cultural comparison.

Med Decis Making. 31,444. doi:

10.1177/0272989X10373805

63. Jeppesen K.M. et.al (2009). Screnning

questions to predicts limited health literacy: A

cross-sectional study of Patients with diabetes

mellitus. Ann Fam Med. 7(1), 24-31.

64. Hanchate A.D. et.al (2008). The

demographic assessment for health literacy

(DAHL): A new tool for estimating association

between health literacy and outcomes in

national surveys. J Gen Intern Med. 23(10),

1561-6.

65. Carlos E. et.al (2004). Literacy and

Numeracy Skills and Anticoagulation Control.

American Journal of the Medical Sciences.

328(2), 88-93.

66. Sorensen K. et.al (2012). Health literacy and

public health: A systematic review and

integration of definitions and models. BMC

Public Health. 12:80. doi: 10.1186/1471-2458-

12-80.