The prevalence of person-perceived participation restriction

in community-dwelling older adults

Ross Wilkie, George Peat, Elaine Thomas & Peter CroftPrimary Care Sciences Research Centre, Keele Universtity, Keele, Staffordshire, ST5 5BG, United Kingdom(E-mail: r.wilkie@cphc.keele.ac.uk)

Accepted in revised form 4 May 2006

Abstract

Objective: To estimate the prevalence, nature and distribution of person-perceived participation restriction,in community-dwelling older adults. Method: Population based cross-sectional postal survey of 11,055adults aged 50 years and over in North Staffordshire, United Kingdom. Person-perceived participationrestriction was measured using the Keele Assessment of Participation which covers 11 different aspects oflife mapped to the World Health Organization�s International Classification of Functioning. Four-weekperiod prevalence was calculated for restriction in any, multiple and for each aspect separately. Prevalenceestimates were calculated for the total sample, and for each age and gender stratum. Results: A total of7,878 subjects responded (adjusted response – 71.3%). The 4-week period prevalence of any participationrestriction was 51.8%; 3.3% had substantial restriction. Participation restriction increased with age(p<0.001) and, for moderate and substantial restriction, was more frequent in women. The prevalence ofrestricted participation in individual aspects of life ranged from 3.8% (work) to 25.9% (mobility outside thehome). Conclusion: Some restriction of participation ‘as and when we want it� is common in the generalpopulation and increases with age, although severe restriction only affects a minority. The distribution ofperson-perceived participation restriction is similar to that of impairments and activity limitation incommunity-dwelling older adults.

Key words: General population, Elderly, Participation restriction, Person-perceived, ICF

Introduction

As the proportion of older adults in the generalpopulation rises, ill-health and disability associ-ated with old age will increasingly influence theoverall picture [1]. There are many differentapproaches to measuring disability, and the WorldHealth Organization (WHO) has endorsed theInternational Classification of Functioning, Dis-ability and Health (ICF) with the aim of facili-tating a consistent approach [2]. This frameworkuses disability as an umbrella term for abnormalfunctioning at three separate levels; anatomical/physiological level – impairment; individual level –

activity limitation; societal level – participationrestriction [2].

Of the three levels of disability proposed in theICF, we know least about participation restriction.Participation restriction refers to the societal con-sequences of health conditions and is defined as‘problems an individual may experience ininvolvement in life situations� [2]. Participationrestriction is hypothesised to result from thecomplex interaction between a health condition,the individual, and contextual factors such as thephysical, social and cultural environment [2]. Inattempting to measure it directly, we recognisethat how people function in the context of their

Quality of Life Research (2006) 15:1471–1479 � Springer 2006DOI 10.1007/s11136-006-0017-9

lives (e.g., work and social activities) may be ofmore concern to them than actual impairments ordifficulties with individual tasks [3]. Participationrestriction is an appealing concept for thoseinterested in older populations and the impact ofchronic diseases because, even when health con-ditions and activity limitations are irreversible,there may still be the potential to maintain par-ticipation [4].

Population studies indicate that the prevalenceof many health conditions and impairments [5],and of activity limitation (measured by self-report[5–7] or by objective methods [8]) rises withincreasing age and is higher in women. Whetherthe same pattern exists for participation restrictionis less clear. Population studies of participationrestriction or handicap – the concept from whichparticipation restriction evolved – are not easy toidentify from the health literature. Certain aspectsof them have been measured in population studiesof disability [e.g., 9–12] but are seldom describedas handicap or participation restriction nor fullyevaluated within the ICF framework. An excep-tion is the Gospel Oaks project, where an attemptwas made to measure handicap in its entirety.Their results suggested that handicap did increasewith age, but was reported equally by men andwomen [13].

There are several reasons why the pattern ofparticipation restriction in the population may notsimply follow that of impairments and activitylimitation. Environmental factors may eitherfacilitate or obstruct participation in those with agiven health condition, impairment or degree ofdifficulty. When allowed to judge for themselveswhether they are restricted or not (as opposed tousing some external standard), individuals with thesame health condition, impairment or degree ofdifficulty in a certain task might arrive at differentinterpretations based on experience and expecta-tions. ‘Paradoxical� ratings of good quality of lifehave been found in people with more severe dis-ease and poorer objective function [14, 15] and asimilar phenomenon may exist for rating partici-pation restriction.

Factors both from the environment and behindthe subjective appraisal of participation may alter

over the course of middle and old age. As a simpleexample, the prevalence of lower limb osteoar-thritis increases with age [16], as does difficultywith walking [17]. However, a similar age-relatedincrease in the prevalence of feeling restricted ingetting around outside the home may be offset byenvironmental facilitators such as availability anduptake of public and private transport, or bychanges in how mobile individuals with osteoar-thritis expect to be as they get older.

We have estimated participation restriction in apopulation survey, choosing to measure it fromthe individual�s perspective by enquiring whetherthey take part ‘as much as they want� in a range oflife situations. We present here an estimate of theprevalence and nature of participation restrictionin a cross-sectional sample of older adults in thegeneral population, and its association with ageand gender in this sample.

Methods

Study design and participants

The North Staffordshire Osteoarthritis Project(NorStOP) is a population-based prospectivecohort study of community-dwelling adults aged50 years and over registered with three generalpractices (regardless of the extent or nature of anycontacts with the practice) in North Staffordshire.Ethical approval for the study was obtained fromthe North Staffordshire Local Research EthicsCommittee. Full details of the study protocol havepreviously been reported [18]. In March 2002,baseline self-complete questionnaires about healthwere mailed to all adults aged 50 years and overregistered with the three participating practices. Astandard mailing procedure was used, in which areminder postcard was sent to non-responders2 weeks after the initial mailing, and a repeatquestionnaire sent to remaining non-responders afurther 2 weeks after this. Ninety-eight percent ofthe general adult population in North Stafford-shire is Caucasian with levels of health deprivationand disability below the average for England andWales [19, 20].

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Data collection

The questionnaire collected information ondemographic, socioeconomic and general healthcharacteristics, including Short Form-12 instru-ment (SF-12) [21]. Participation restriction wasmeasured by the Keele Assessment of Participa-tion (KAP) [22]. This is a recently developed11-item self-complete instrument, designed tomeasure participation in a number of areas of lifefrom the perspective of the individual. It covers thefollowing aspects, mapped to domains and sub-domains of the World Health Organization�sInternational Classification of Functioning:mobility within the home, mobility outside thehome, self-care, looking after belongings, lookingafter the home, looking after dependants, inter-personal interaction, managing money, work,education, and social activities [22]. Items arephrased to capture performance (‘I have�), indi-vidual judgement and the nature and timeliness ofparticipation (‘as and when I have wanted�).Responses were on a five point ordinal scale(i.e., ‘All of the time� ‘Most of the time� ‘Some ofthe time� ‘A little of the time� ‘None of the time�).Filter questions are included in four items (lookingafter dependants, work, education and socialactivities) to allow responders to indicate if theseitems were relevant or not, since in pilot studiesthese were identified as not applying to everyone�slives. The reliability and validity of the KAP hasbeen established as adequate for providing esti-mates of person-perceived participation restrictionin population studies [22].

Statistical analysis

Participation restriction was defined by a responseof ‘some of the time� or less and calculated forresponders who had completed all KAP items. The4-week period prevalence of participation restric-tion was calculated overall and within age andgender specific strata for (i) any participationrestriction (participation restriction in at least oneaspect of life), (ii) minimal (1–3 restricted aspectsof life), moderate (4–6 aspects of life) and sub-stantial (7–11 aspects of life) amounts of partici-pation restriction and (iii) each of the 11 aspects oflife separately.

Differences between age groups in each of theabove prevalence estimates of participationrestriction were tested using a chi-square test (v2),and, if significant, followed by a chi-square test forlinear trend. Gender differences were examined bypercentage difference with 95% confidence inter-vals.

To estimate the effects of age on the gender-specific prevalence estimates of the amounts ofparticipation restriction, age-specific prevalencewas calculated separately for men and women foreach category of participation restriction. A crudesummary ratio of the observed prevalence in wo-men to men was also calculated and expressedrelative to a figure of 100 as representing no dif-ference between men and women. Indirect stan-dardisation was used to calculate an age-adjustedratio of female to male prevalence [23].

Results

A total of 11,055 questionnaires were mailed, and7,878 completed forms returned (adjustedresponse = 71.3%). Of the non-responders, 255people declined to take part, 109 did not completethe questionnaire due to ill health, and no contactwas received from 2,813 people. Responders weremore likely to be female than were non-respond-ers. Non-response was highest in the youngest(50–59 years) and oldest (80+ years) age groups.However, survey responders as a whole were verysimilar in general health, age, gender and maritalstatus to UK norms, suggesting that there was nosubstantial non-response bias [24, 25].

Fifty-six percent of responders were female [26].The overall mean (standard deviation) age was66.3 years (10.3 years). The mean age of femaleresponders was slightly higher (66.9 years) thanthat of male responders (65.5 years). Twenty-sixpercent of the sample were currently working,proportionately more males than females (differ-ence 9.1%; 95% CI: 7.1%, 11.1%). Males weremore likely to be in higher managerial/professionaloccupations and less likely to be in semi-routineoccupations, when compared with females. Themean SF-12 mental and physical health scoreswere 48.8 (SD: 11.2) and 40.7 (SD: 12.5), respec-tively, similar in men and women. Physical healthSF-12 scores fell (indicating poorer health) with

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increasing age for men and women (e.g., 44.7 forwomen aged 50–59 years, 31.6 for women aged80+ years). However, mental health scores didnot change with age in either gender.

Prevalence of any participation restriction

A total of 7,259 (92.1%) responders completed allKAP items. A total of 3,759 reported participationrestriction in one or more aspects of life (4-weekprevalence of any participation restriction =51.8%) (Table 1). This increased linearly with age(p<0.001) and was more common in women thanin men (% difference: 6.6% [95% CI: 4.2, 8.9]).

Prevalence of participation restriction in multipleaspects of life

A total of 2,697 (37.2%) indicated participationrestriction in one-to-three (minimal), 822 (11.3%)in four-to-six (moderate) and 240 (3.3%) in seven-to-eleven (substantial) (Table 1). For all threecategories, prevalence increased linearly with age(p<0.001) in both men and women. There was nodifference in the prevalence of minimal amounts ofrestriction between men and women (% difference:0.9% [95% CI: 1.4, 3.1]). However, moderate andsubstantial amounts of participation restriction

were significantly more common in women than inmen (% difference: 3.4 [95% CI: 1.9, 4.8] and 2.3[95% CI: 1.5, 3.1]).

These patterns were confirmed after indirectstandardisation for age, the ratios of female:maleprevalence of minimal, moderate and substantiallevels of participation restriction being 101, 129,205, respectively (Table 2). Gender differences in-creased with age.

Prevalence of participation restriction in each aspectof life

The most common participation restriction was inmobility outside the home (25.9%). The preva-lence estimates for the other aspects of life were:managing money (19.2%), interpersonal interac-tion (16.2%), looking after the home (15.8%),mobility within the home (14.1%), social activities(13.6%), looking after belongings (11.5%), self-care (10.6%), looking after dependants (5.4%),education (4.1%), and work (3.8%).

The prevalence of participation restriction in-creased with age in seven of the items, but in two(work and education) the prevalence was highestin the 50–59 age group and decreased at older ages(Figure 1). For social activities and looking afterdependants, there was no change with age.

Table 1. Four-week period prevalence of participation restriction; overall and stratified by age and gender

Categories of

amounts of

participation

restriction

All responders

(n = 7259)

Age group Gender

50–59 60–69 70–79 80+ v2 (trend)* p Female Male % difference

(95% CI)a

Any (‡1 aspect)

No. 3759 1051 1029 1057 548 265 <0.001 2218 1541

% 51.8 44.0 46.9 57.2 75.5 54.7 48.1 6.6 (4.2, 8.9)

Minimal (1–3 aspects)

No. 2697 788 779 743 387 59.6 <0.001 1523 1174

% 37.2 32.8 35.5 40.2 46.7 37.5 36.6 0.9 ()1.4, 3.1)

Moderate (4–6 aspects)

No. 822 195 193 245 189 121.0 <0.001 520 302

% 11.3 8.1 8.8 13.3 22.8 12.8 9.4 3.4 (1.9, 4.8)

Substantial (7–11 aspects)

No. 240 68 57 69 69 14.1 <0.001 175 65

% 3.3 3.3 2.6 3.7 3.7 4.3 2.0 2.3 (1.5, 3.1)

*v2 (trend) calculated with 1 degree of freedom.aCI, Confidence interval.

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In most aspects of life, the prevalence ofrestriction was significantly greater in women thanmen. The exceptions were education, whererestriction was significantly more frequent in men,and work and looking after dependants, wherethere were no significant differences between menand women. The rank order of frequency of

restriction in different aspects of life was similarfor men and women. For both men and women,mobility outside the home was most frequentlyrestricted (28.8% for women; 22.3% for men),whilst restrictions in work (3.8% in both men andwomen) and education (3.5% in women; 4.8% inmen) were the least commonly reported.

0% 10% 20% 30% 40% 50% 60%10%20%30%40%50%60%

Prevalence of participation restriction Prevalence of participation restriction

Prevalence of participation restrictionPrevalence of participation restriction

Male Female Male Female

Male FemaleMale Female

Aged 70-79 years

0% 10% 20% 30% 40% 50% 60%10%20%30%40%50%60%

Aged 80 + years

0% 10% 20% 30% 40% 50% 60%10%20%30%40%50%60%

Aged 60-69 years

Mobility within the homeMobility outside the home

Managing money

Education

Interpersonal interaction

Work

Looking after dependants

Self-careLooking after the homeLooking after belongings

Social activities

0% 10% 20% 30% 40% 50% 60%10%20%30%40%50%60%

ASPECT OF LIFE

Mobility within the homeMobility outside the home

Managing money

Education

Interpersonal interaction

Work

Looking after dependants

Self-careLooking after the homeLooking after belongings

Social activities

ASPECT OF LIFE

Mobility within the homeMobility outside the home

Managing money

Education

Interpersonal interaction

Work

Looking after dependants

Self-careLooking after the homeLooking after belongings

Social activities

ASPECT OF LIFEMobility within the homeMobility outside the home

Managing money

Education

Interpersonal interaction

Work

Looking after dependants

Self-careLooking after the homeLooking after belongings

Social activities

ASPECT OF LIFE

Aged 50-59 years

Figure 1. Four-week prevalence of participation restriction for each aspect of life stratified by age and gender.

Table 2. Comparison of 4-week period prevalence of participation restriction for men and women using indirect standardisation

Categories of

amounts of

restricted areas

Age group Observed

number of

women

Observed

number of

men

Crude

ratioaExpected

number of

women

Adjusted

ratiob

50–59 60–69 70–79 80+

F M F M F M F M

Minimal (1–3 areas)

No. 428 360 417 362 425 318 253 134 1523 1174 102 1513 101

% 33.6 32.3 35.0 36.0 40.5 39.8 46.5 47.3

Moderate (4–6 areas)

No. 1.7 88 110 83 164 81 139 50 520 302 136 402 129

% 8.4 7.9 9.2 8.3 15.6 10.1 25.6 17.7

Substantial (7–11 areas)

No. 47 21 39 18 51 18 38 8 175 65 215 85 205

% 3.7 1.9 3.3 1.8 4.9 2.3 7.0 2.8

Total number who completed all KAP items

No. 1275 1115 1190 1005 1048 799 544 283 4057 3202 4057

% 100.0 100.0 100.0 100.0 100.0 100.0 100.0 100.0

aRatio of observed prevalence of females to the observed prevalence of males for each category of the amount of participation

restriction.bRatio of observed prevalence in females to expected prevalence in females for each category of the amount of participation restriction.

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Discussion

We have used a simple self-report instrument toestimate participation restriction in an older pop-ulation sample. We measured participationrestriction from the perspective of the individual asit potentially gives a more accurate account andgreater understanding of participation restrictionthan a societal perspective in which participation iscompared against a normative objective standard[27]. We have shown that it is common and ishigher in the oldest ages and in women. However,the extent to which different areas of life are af-fected varies greatly, with restriction in some areasrather low. Although some restriction is common,25% of those aged 80 years and over remain freeof participation restriction in most areas of theirlife.

Despite their conceptual contrasts, participationrestriction appears to have a similar prevalenceand distribution in the older population as thatreported for activity limitation and impairments[5–7]. Referring to the conceptual model of par-ticipation restriction, the age-related increase inchronic disease and activity limitation does notappear to be offset by environmental factors (e.g.,the provision of assistance or assistive-devices) andpersonal factors (e.g., expectations that function-ing should be difficult), sufficiently to maintainparticipation to the extent that older people wish;participation restriction also increases with age.However, participation restriction offers a per-spective different to measures of impairment andactivity limitation alone, and provides one way inwhich the impact of health conditions on thefunctioning of older adults in the contexts of theireveryday lives can be described.

Our study provides evidence that the oldest oldand women are more vulnerable with respect totheir participation in everyday life, and highlightsthe large number of older adults who may benefitfrom interventions designed to improve participa-tion. Mobility outside the home was the mostcommon area of participation restriction and,however measured, is clearly a major concern inthis age-group, warranting specific investigationsinto this form of disability [28, 29]. Work was theleast common area of participation restriction andthe decreasing prevalence with increasing age mayreflect the increasing proportion of older adults

who are retired and no longer consider engaging inemployment.

The general practices used in this study werelocated in urban areas and the number ofnon-white groups were small, limiting the gener-alizability of these estimates of participationrestriction. The postal method may have preventedcollection of information from those with cogni-tive or physical impairment, who may participateless than those able to complete questionnaires.We estimated the effects of non-response, byregarding ‘late� responders (those who respondedafter receiving a reminder postcard or question-naire) as a representative sample of non-respond-ers [30]. The prevalence of participation restrictionwas higher in the ‘late� responders than in ‘early�responders, suggesting that our reported preva-lence of any participation restriction was indeed anunderestimate (Table 3).

Missing data (619 (7.9%) of 7,878 participantsdid not complete all KAP items) may also have ledto an underestimate of prevalence, although theeffects of this are likely to be small. In comparisonto those included in the analysis, those who did notcomplete all KAP items were older (mean age(years): 70.2 cf 70.0), were more likely to be female(58.0% cf 55.9%) and had lower general health(mean SF-12 physical functioning score: 38.6 cf40.8; mean SF-12 mental functioning score: 46.3 cf48.9).

The prevalence in four areas (looking after de-pendants, work, education and social activities)may have been affected by the inclusion of ascreening question. Responders who indicated inthe screening question that they chose not toparticipate in these areas are classified as partici-pating. However, misclassification can occur, forexample, responders may choose not to work dueto a health condition or working conditions actingas a barrier, and are erroneously classified asparticipating in work ‘as and when they want.�Therefore, the screening questions may lead to anunderestimate of prevalence in these aspects of life.

The estimates of participation restriction werelower than those reported for handicap in theGospel Oaks project [13], overall (63% indicatedmore than low levels of handicap in the GospelOaks compared with 51.8% indicating some par-ticipation restriction in at least one aspect of life inour study) and for individual items (range: 38–75%

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in Gospel Oaks and 3.8–25.9% in our study).Despite the differences in the methods between thetwo studies (interviews were used in the GospelOaks study, incorporating the London HandicapScale, which measures handicap from a societalperspective [31]), restricting the analysis in ourstudy to the same age group as the Gospel Oakspopulation (i.e., adults aged 65 years and over)resulted in similar prevalence estimates (prevalenceof no participation restriction in our study – 41.5%(95% CI: 40.4, 42.0), prevalence of low levels ofhandicap in the Gospel Oaks study – 37% (95%CI: 33.3, 40.7).

Our study has applied the concepts of the WorldHealth Organization model to population mea-surement of participation restriction. Furtherinvestigation is now warranted to determine thepotential determinants (e.g. health conditions,impairments, activity limitations, environmentaland personal factors) of participation restriction inthe general population, which may explain itsnature and distribution and lead to the develop-

ment of interventions designed to reduce thiscommon form of disability in community-dwellingolder adults.

Key points

• Participation restriction is common in olderadults; 51.8% reported restriction in at leastone aspect of life.

• Participation restriction increased with age, asdid the number of areas of life in which partic-ipation was perceived to be restricted. How-ever, one-quarter of those over 80 years andover do not perceive themselves as restricted intheir participation in most areas of life.

• Women are more likely to report moderateand substantial amounts of participationrestriction than men.

• The distribution of person-perceived participa-tion restriction is similar to that for impairmentand activity limitation in community-dwellingolder adults.

Table 3. Observed numbers of responders and the 4-week period prevalence of any participation restriction, overall and stratified by

early and late response; the estimated number of non-responders and in the whole sample population with any participation restric-

tion

Age

group

Observed Estimated

Number (%) of

‘early responders�with any participation

restriction

Number (%) of

‘late responders�with any participation

restriction

Number of

all responders

(early + late)

with any participation

restriction

Number of

non-responders

with any

participation

restriction

Number in the

whole sample

population

(all responders +

non-responders)a

No. (%) No. (%) No. No. No.

50–59 years

Female 318 (43.9) 264 (48.0) 582 266 848

Male 240 (41.3) 229 (42.9) 469 308 777

60–69 years

Female 342 (44.9) 224 (52.3) 566 196 762

Male 276 (43.5) 187 (50.4) 463 206 669

70–79 years

Female 404 (58.6) 236 (65.7) 640 217 857

Male 257 (48.3) 160 (59.9) 417 162 579

80+ years

Female 263 (76.7) 167 (83.9) 430 328 758

Male 129 (66.2) 63 (71.6) 192 92 284

Total 2229 (50.0) 1530 (54.7) 3759 (51.8)b 1775 (54.7) 5534 (52.2)c

aTotal number of responders and non-responders was 10 611, due to missing data (n = 619).bObserved prevalence in all responders.cEstimated prevalence in the sample population (responders and non-responders).

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Acknowledgements

This study is supported financially by a Pro-gramme Grant awarded by the Medical ResearchCouncil, UK (Grant code: G9900220) and byfunding secured from the North StaffordshirePrimary Care R&D Consortium for NHS servicesupport costs. The authors would like to thankthe administrative and health informatics staff atKeele University�s Primary Care SciencesResearch Centre. We would also like to thankthe doctors, staff and patients of the participat-ing general practices and Professor Carol Jaggerfor her helpful comments on the drafting of thispaper.

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