Comparing contents of outcome measures in cerebral palsy using the international classification of functioning (ICF-CY): A systematic review

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Official Journal of the European Paediatric Neurology Society

Review article

Comparing contents of outcome measures in cerebral palsy using the international classification of functioning (ICF-CY): A systematic review Veronica Schiariti a,*, Anne F. Klassen b, Alarcos Cieza d,e,f, Karen Sauve a, Maureen O’Donnell a, Robert Armstrong g, Louise C. Maˆsse c a

Department of Pediatrics, University of British Columbia, Vancouver, British Columbia, Canada Department of Pediatrics, McMaster University, Hamilton, Ontario, Canada c School of Population and Public Health, University of British Columbia, Vancouver, British Columbia, Canada d Faculty of Social and Human Sciences, University of Southampton, United Kingdom e Department of Medical Informatics, Biometry and Epidemiology, Research Unit for Biopsychosocial Health, LudwigMaximilians-University, Munich, Germany f Swiss Paraplegic Research, Nottwil, Switzerland g The Aga Khan University, East Africa Nairobi, Kenya b

article info

abstract

Article history:

The International Classification of Functioning children and youth version (ICF-CY) provides a

Received 25 February 2013

universal framework for defining and classifying functioning and disability in children

Accepted 7 August 2013

worldwide. To facilitate the application of the ICF in practice, ICF based-tools like the “ICF Core Sets” are being developed. In the context of the development of the ICF-CY Core Sets for

Keywords:

children with Cerebral Palsy (CP), the aims of this study were as follows: to identify and

Cerebral palsy

compare the content of outcome measures used in studies of children with CP using the ICF-

Systematic review

CY coding system; and to describe the most frequently addressed areas of functioning in those

Outcome measures

studies. We searched multiple databases likely to capture studies involving children with CP

International classification of func-

from January 1998 to March 2012. We included all English language articles that studied

tioning

children aged 2e18 years and described an interventional or observational study. Constructs

Content comparison

of the outcome measures identified in studies were linked to the ICF-CY by two trained pro-

Child

fessionals. We found 231 articles that described 238 outcome measures. The outcome measures contained 2193 concepts that were linked to the ICF-CY and covered 161 independent ICF-CY categories. Out of the 161 categories, 53 (33.5%) were related to body functions, 75 (46%) were related to activities/participation, 26 (16.1%) were related to environmental factors, and 7 (4.3%) were related to body structures. This systematic review provides information about content of measures that may guide researchers and clinicians in their selection of an outcome measure for use in a study and/or clinical practice with children with CP. ª 2013 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved.

* Corresponding author. Department of Pediatrics, University of British Columbia, Room F509, 4480 Oak Street, Vancouver, British Columbia, V6H 3V4, Canada. Tel.: þ1 604 875 2000x5438; fax: þ1 604 875 3569. E-mail address: [email protected] (V. Schiariti). 1090-3798/$ e see front matter ª 2013 European Paediatric Neurology Society. Published by Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.ejpn.2013.08.001

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Contents 1. 2.

3.

4.

5. 6. 7. 8.

1.

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Materials and methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. Search strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.2. Articles processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.3. Data extraction and ICF-CY linking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.4. ICF-CY coding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 2.5. Data analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.1. Articles characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.2. Overview of measures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 3.3. Most frequently covered areas of functioning: ICF-CY categories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7 Discussion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.1. Content comparison of outcome measures used in CP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.2. Selecting the most appropriate outcome measure for CP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 4.3. Towards the ICF-CY Core Sets for CP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 4.4. Limitations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Author contribution . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Conflict of interest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Acknowledgment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 Supplementary data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

Introduction

Cerebral Palsy (CP) describes a group of development disorders of movement and posture commonly associated with other co-morbidities (e.g. sensory, cognitive, communication).1 CP is the most common cause of severe physical disability in childhood.2 In developed countries, the incidence of CP is estimated at 2e2.5 per 1000 live births.3,4 Given the complexity of CP, these children utilize multiple health and educational resources. Advancing the breadth of knowledge related to this neurodevelopmental disorder is necessary if we are to improve the quality of function, health and educational outcomes. What remains unclear is how to select the most appropriate outcome measure in studies of children with CP. Various outcome measures have been used to assess functional abilities, participation and quality of life in this population5e8; however, there is lack of consensus about which are the most appropriate to use to measure function and overall health of children with CP. Lack of understanding of the functional areas covered by each outcome can make it challenging to evaluate response to treatments and compare results across studies. While it is important to look at the psychometric properties of the measures when selecting an outcome measure, it is also important to consider conceptualization of constructs and the content used to measure these. The International Classification of Functioning children and youth version (ICF-CY)9 can potentially serve as a useful tool to help standardize the ultimate selection of outcome measures in studies involving children with CP.

The ICF-CY was developed by the World Health Organization (WHO) as a classification system that defines health and functioning of children using a uniform coding system.9 The ICF framework can be used as a common reference to compare the content of outcome measures,10,11 such as self-reported measures (e.g. quality of life questionnaires) or clinical measures (e.g. gait analysis). Mapping the content of outcome measures onto the ICF-CY coding system provides clinicians and researchers with information about the areas of functioning, disability and health that are covered by those measures. This information can help standardize clinical assessments. In order to move the field of CP forward, it is crucial that a consistent assessment approach is used across disciplines and geographical settings. The ICF framework is based on a bio-psycho-social model covering functioning and disability with its components body structure, body functions, activities and participation as well as identifying the need to consider context, represented through personal and environmental factors.9 The ICF-CY consists of 1685 so-called categories (unit of analysis). The large number of categories limits its utility in research and clinical settings as professionals do not find it easy to incorporate into their daily practices.9 To improve its application, the classification must be tailored to the needs of different users, which is the primary motivation behind the development of the ICF Core Sets.12 Specifically, the development of ICF Core Sets uses an evidence-based methodology to identify the most relevant categories from the entire set of categories. Currently, ICF Core Sets have been created for thirty-three chronic conditions common to adults (e.g. osteoarthritis,

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multiple sclerosis, sleep disorders).12e15 The Core Sets standardize what should be measured and reported for a given population and thereby facilitate the use of the classification system.12 Each Core Set consists of a brief (20e30 categories) and a comprehensive version (70e100 categories). The Core Sets have been used to recognize patient’s needs, to report and describe functioning in different settings (acute, rehabilitation, etc) and to assess response to interventions.12,16,17 To date, no Core Sets have been developed for children. Our research team, in collaboration with the ICF Research Branch of the WHO Collaborating Centre for the Family of International Classifications, is leading the development of the ICF-CY Core Sets (brief and comprehensive versions) for children with CP. Following the methodology endorsed by the WHO for ICF Core Sets development,12 four independent studies reflecting the researchers’ perspectives, the professionals’ perspectives (international expert survey),18 the children and caregivers’ perspectives and the clinical perspectives are required to gather the evidence to support the final selection of the categories. The information compiled is subsequently used to inform an international consensus process. The findings of this systematic review will contribute the researchers’ perspectives towards the development of the ICF-CY Core Sets for children with CP. In the context of the development of the ICF-CY Core Sets for children with CP, the objectives of this study were as follows: [1] to determine the most widely used outcome measures in studies with children with CP; [2] to identify and compare the content of those measures using the ICF-CY coding system; and [3] to identify the most frequently addressed areas of functioning in studies with children with CP.

2.

Materials and methods

We conducted a systematic review of the literature for original intervention and observational studies that included children with CP. We identified all clearly defined outcome measures used in those studies and described the content of those measures using the ICF-CY language. Finally, we identified the most commonly covered areas of functioning in studies with children with CP.

2.1.

Search strategy

The following databases were searched covering the period from January 1998 to March 2012: Medline, PsycINFO, Embase, Central and CINAHL. Thesaurus terms and keywords were used. Examples of terms searched include the following: “CP, treatment/assessment outcome, performance test, questionnaire, health status, function adjacent (assessment or/motor or/skills), health related quality of life (HRQOL), and quality of life (QOL)”, (searches available online, Appendix 1). Inclusion criteria consisted of the following: studies on children and/or youth with CP, study with the particular designs (randomized controlled trials [RCT], before/after studies, cross-sectional studies, longitudinal observational studies, qualitative studies), and studies

3

published in English. Systematic reviews, validity/reliability studies, phase I/II clinical trials, secondary analysis of published data, and protocols were excluded.

2.2.

Articles processing

Results (n ¼ 862 citations) from our search were exported to a reference system (RefWorks) and duplicates were removed. Screening was performed by two screeners who worked independently (VS, KS). A third person (AK) resolved any conflicts. Screening was performed using the Systematic Review System (SRS, Mobious-Analytic). We applied a stepwise screening process, first applying the above inclusion/exclusion criteria to all title/abstracts (n ¼ 698), and then full text articles for the included abstracts (n ¼ 314) were retrieved and inclusion/exclusion criteria was applied resulting in the identification of 231 articles, full list upon request (Fig. 1).

2.3.

Data extraction and ICF-CY linking

We followed a four-step procedure for data processing as follows: [1] extracting study information e for all the studies (n ¼ 231) we extracted average age of participants, age range, gender, type of CP, Gross Motor Function Classification System (GMFCS) levels, study design, outcome measures, self/proxy report, and country where the study was conducted; [2] classification of outcome measures to determine whether it was a multiple-item or single-item measure, out of the 289 outcome measures identified, 129 were multiple-item and 160 were single-item measures; [3] outcome measures retrieval, we were able to obtain 96 out of the 129 multiple-item measures (reasons for no retrieval included: language other than English, adaptation of an original measure, adhoc questionnaires, and copyright issues preventing use) and all of the single-item measures; and [4] linking to the ICF-CY, we linked 78 out of 96 multiple-item (reason for not linking included: structure of the measure) and all 160 single-item measures (Fig. 1). Two health professionals working independently linked each item to the domains of the ICF-CY using the coding process described below and then resolved disagreements by consensus.

2.4.

ICF-CY coding

We followed the ICF linking guidelines proposed by Cieza et al.,19 which has been applied to a variety of outcome measures in adults and a few pediatric HRQOL measures (e.g. DISABKIDS, cancer measures, CP disease-specific measures, and generic patient-reported outcomes).20e22 The content of the measure is linked to the two parts of the ICF-CY. Part 1 covers functioning and disability and includes the components of body functions (b) and structure (s) and activities and participation (d). Part 2 covers contextual factors and includes the components environmental factors (e) and personal factors (pf). In the classification, the letters b, s, d and e, which refer to the component of the classification, are followed by a numeric code starting with the chapter number (one digit) followed by a second, third, or fourth level code (adding two and one digit, respectively). For example, the component ‘activity and participation’ of the classification contains the following codes: d5-Self-care (first/chapter level), d570-

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MEDLINE EMBASE PSYCINFO CENTRAL CINAHL

Citations N=862 Excluded N=164 Reasons for exclusion: duplicates, publication year before 1998 Title/Abstract screening N=698

Full text screening N=314

Total articles for instruments retrieval N=231

Excluded N=384 Reasons for exclusion: language other than English, Study design did not meet inclusion criteria, population other than CP, population no children or youth Excluded N=83 Reasons for exclusion: duplicates, full text, Unobtainable, and as above

Total outcome measures N= 289

Single-Item measures N= 160

Multiple-Item measures N=129

Linked to ICF-CY N=238

Single-Item measures N= 160

Excluded N=51 Reason for no retrieval or not linking: Language other than English, adaptations of original measures, selfdeveloped questionnaires, copyright

Multiple-Item measures N=78

CP; Cerebral Palsy, ICF-CY; International Classification of Functioning children and youth version Fig. 1 e Search, screening and linking steps.

Looking after one’s health (second level), d5702-Maintaining one’s health (third level), d57021-Seeking advice or assistance from caregivers (fourth level). Since “pf’ are not classified yet, to identify them we used the definition that is provided in the ICF. This linking procedure was performed separately by two trained assessors (VS, KS). Subsequently, consensus between the assessors was required. In case of disagreement, a third assessor (AC) was consulted. If an item contained more than one concept, each concept was linked separately. Items that were too general to be coded were assigned “not definable” (nd). For example, “overall health” (h) is too general to code, therefore, it was coded as “nd-h”. Finally, if the concept was not captured by the ICF-CY classification, it was labeled “not covered” (nc).

Before linking each measure, the purpose of the measure and its manual were reviewed, a decision was made as to whether the full content (individual items) could be linked to the ICF-CY or only the purpose or the main domains could be linked. Only original versions of the measures were linked. Some measures were not suitable for linking (e.g. Goal Attainment Scaling [GAS] as the content varies from child to child). If a measure had different age-specific versions, the most frequently used version was linked (e.g. PedsQL school-aged version was only linked). Finally, some measures were not available due to copyright, and thus only the main domains of those measures as described in the articles were linked (e.g. WeeFIM). The reliability of the linking process was assessed using the Kappa coefficient23 computed in SAS (SAS Institute Inc.). The overall inter-

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coders reliability of the linking process was 0.74 (95% confidence interval 0.73e0.75).

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Table 1 e Characteristics of included papers, N [ 231. Publication year

2.5.

Data analysis

For each of the identified instruments, we calculated the frequency a measure had been reported and the frequency with which its items/domains addressed b, s, d, e and pf, and other concepts linked to nc and nd. If an ICF-category was assigned repeatedly in a measure, the category was counted only once. Similar to previous studies,10,11,22,24e29 ICF-CY categories were used to identify and quantify the most relevant areas of body functions and body structures, activity and participation, and environmental factors for children with CP. Descriptive statistics was used to calculate the frequency a category was represented in the studies. ICF-CY categories included in less than twenty percent (>80th percentile) of the outcomes were disregarded, the same arbitrary cut-off used in previous studies.26

3.

Results

3.1.

Articles characteristics

The median age of the study population was 8.6 years. Distribution by age groups is shown in Appendix 2 (supporting information online), which shows that school-aged children was the prevalent studied group. Spastic diplegia and quadriplegia were the common studied CP types. Overall, 58% of the papers used the GMFCS classification to characterize their study population. The majority of the studies were intervention studies. Proxy report was the predominant data collection method. Most studies were conducted in USA, followed by Australia and Canada (see Table 1).

3.2.

Overview of measures

Out of the 78 multiple-item measures linked to the ICF-CY, the Gross Motor Function Measure (GMFM)30 was the most frequently measure used, followed by the Pediatric Evaluation of Disability Inventory (PEDI)31 and the Child Health Questionnaire (CHQ).32 ‘‘Mobility of joints’’ was the single-item measure most frequently used, followed by ‘‘spasticity’’ and ‘‘gait pattern’’ (full list shown in Appendix 3, supporting information online). Table 2 provides a list of the 15 most used multiple-item measures linked to the ICF-CY. (full list showing all multiple-item measures is included in Appendix 4, supporting information online). Most of the measures covered the components of activity and participation, and body functions. Only a few of the measures covered most of the ICF-CY components including body functions, activity and participation, environmental and personal factor (e.g. CHQ, Pediatric Outcomes Data Collection Inventory (PODCI),33 Cerebral Palsy Quality of Life questionnaire for children (CPQOL)34, and KIDSCREEN).35 The majority of the single-item measures assessed body functions (Appendix 3). Table 3 shows the content of the 15 most used multipleitem measures at the chapter level for the components body functions, activity and participation and environmental

1998e2004, N (%) 83(35.9) 2004e2012, N (%) 148(64.1) Characteristics of study population Gender, male % 59 Age, median (interquartile range) in years 8.6(4.5) Age range, median minimum and maximum in years 4e13 Study Sample Size, N (%) Group 1 (20 participants) 82(35.5) Group 2 (21e100 participants) 101(43.7) Group 3 (101e400 participants) 36(15.6) Group 4 (401e900 participants) 12(5.2) Type of CP, N (%)a Spastic diplegia 154(66.6) Spastic quadriplegia 110(47.6) Spastic hemiplegia 111(48.1) Dystonic 4(1.7) Ataxic 23(10) Others 89(38.5) a % Do not add up to 100% as papers included combinations of CP types Total number of papers reporting GMFCS levels, N (%) 134(58) Number of papers reporting GMFCS by level, Na GMFCS I 96(41.6) GMFCS II 100(43.3) GMFCS III 109(47.2) GMFCS IV 92(39.8) GMFCS V 75(32.5) Study Design Intervention studies, N (%) 139(60.2) Randomized controlled trials 44 Before/after design 59 Others 36 Observational studies, N (%) 91(39.4) Cross-sectional studies 42 Cohort studies 16 Others 33 Qualitative study, N (%) 1(0.4) Proxy vs self reportb Proxy report, N (%) 219(94.8) Combination proxy and self report, n (%) 28(12.1) Country, N (%) USA 64(27.7) Australia 23(10.0) Canada 23(10.0) United Kingdom 19(8.0) Netherlands 17(7.3) Others 86(37.0) a

% Do not add up to 100% as papers included combinations of GMFCS levels. b Do not add up to 100%, some studies use both proxy and self report.

factors respectively. (full list shown in Appendix 4, supporting information online). The component body structures is not shown as it was rarely covered by the measures. Content of measures differed significantly in their representation of the ICF-CY chapters in all components, for example in the component activity and participation the GMFM only covered chapter d4 “mobility” compared to the PEDI which included all chapters. Overall, the most prevalent chapters were: b1 “mental functions”, d4 “mobility”, d5 “self-care” and e1 “products and technology”. Supplementary Tables A5I to

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Table 2 e Distribution of contents of the 15 most used multiple-item measures by ICF-CY component. Name (abbreviation)a

Melbourne assessment of upper limb function (MAULF) Pediatric evaluation of disability inventory (PEDI) The Pediatric quality of life inventory (PEDSQL) Pediatric outcomes data collection inventory (PODCI) Physician’s rating scale (PRS) Quality of upper extremity skills test (QUEST) Strength and difficulties questionnaire (SDQ) Vineland adaptive behavior scales (VABS) WeeFIM

a

B N (%)

S N (%)

A&P N(%)

EF N(%)

PF Others Total number N(%) N(%) of unique conceptsb

Linked to ICF-CY

0

0

23(100)

0

0

Items

21(35)

0

27(45)

4(6.7)

1(1.7) 7(11.7)

60

5

55

0

23

19

109

8

12

0

0

30(100)

0

0

0

30

10

32

2(11.8)

0

15(88.2) 0

0

0

17

Items

92

88

3(12)

0

22(88)

0

0

0

25

Items

5

10

7(46.7)

0

3(20)

2(13.3) 1(6.7) 2(13.3)

5

4

0

0

4(100)

0

35

199

13(17.8)

0

9

23

6(30)

12

87

9

15

Brief description of measure

Self-report measure of children’s participation in recreation and leisure activities outside of mandated school activities Items Multidimensional quality of life instrument focuses on physical and psychosocial functioning and well-being. Domains Detects change in a client’s self-perception of occupational performance over time. Assesses the functional walking level of a child

Measures change in gross motor function over time in children with cerebral palsy. Domains Assesses children’s and adolescents’ subjective health >and well-being, applicable to healthy and chronically ill children Domains Measures quality of unilateral upper limb movement in children with neurological conditions,

0

0

4

58(79.5) 2(2.7)

0

0

73

Items

0

10(50)

0

1(5)

20

Items

6(13)

0

32(69.6) 5(10.9) 1(2.2) 2(4.3)

46

Items

6

1(100)

0

0

0

0

0

1

Items

Quantitative observational scale that evaluate gait

13

7

5(71.4)

0

2(28.6)

0

0

0

7

Items

5

34

10(40)

0

12(48)

1(4)

1(4)

1(4)

25

Items

Evaluates movement patterns and hand function in children with cerebral palsy Brief behavioural screening questionnaire

8

61

7(13)

0

44(81.5) 1(1.9)

1(1.9) 1(1.9)

54

Items

4

18

1(5.6)

0

17(94.4) 0

0

18

3(15)

0

Assesses key functional capabilities and performance in children by observing mobility, self-care and social function Multidimensional measure of HRQOL in healthy children and adolescents and acute and chronic health conditions. Subjective measurement assesses outcomes in pediatric musculoskeletal conditions.

A measure of adaptive behavior from birth to adulthood. Domains Measures functional performance in three domains: self-care, mobility and cognition.

Measures order by abbreviation alphabetical order. Total number of meaningful concepts without duplications per measure. Full list of multiple-item measures is shown in Appendix 4. Abbreviations: B, body function; S, body structure; A&P, activity and participation; EF, environmental factors, PF, personal factors; ICF-CY, International Classification of Functioning, Disability and Health children and youth version. *Other ¼ not definable plus not covered by the ICF-CY. b

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Children’s assessment of participation and enjoyment (CAPE) Child health questionnaire (CHQ) Canadian occupational performance measure (COPM) Gillette Functional assessment questionnaire (FAQ) Gross motor function measure (GMFM) KIDSCREEN

N of citations Items or where measure domains was used used in analysis

7

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Table 3 e Representation of ICF-CY chapters for the components body functions, activity and participation and environmental factors included in the 15 most used multiple-item measures. Multiple-item measuresa

ICF-CY chapters Body functions Chapters names b1 Mental functions b2 Sensory functions/ pain b3 Voice/speech b4 Cardiorespiratory, haemato/ immunological b5 Digestive, metabolic, endocrine functions b6 Genitourinary reproductive b7 Neuromusculo skeletal and movement-related functions b8 Skin and related structures Activity and Chapters names Participation d1 Learning applying knowledge d2 General tasks demands d3 Communication d4 Mobility d5 Self-care d6 Domestic life d7 Interpersonal interactions/ relationships d8 Major life areas d9 Community, social and civic life Environmental Chapters names factors e1 Products and technology e2 Environment e3 Support and relationships e4 Attitudes e5 Services, systems and policies

GMFM PEDI CHQ QUEST PODCI FAQ PEDSQL PRS COPM VABS CAPE KIDSCREEN MAULF SDQ WEEFIM 0 12 11 1 5 0 4 0 0 7 0 6 0 10 1 0 1 5 0 1 0 1 0 0 0 0 0 0 0 0 0 0

0 0

2 0

0 0

0 0

0 1

0 1

0 0

0 0

0 0

0 0

0 1

0 0

0 0

0 0

0

0

1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

1

0

0

0

0

0

0

0

0

0

0

0

0

3

0

1

4

0

1

0

1

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

0

GMFM PEDI CHQ QUEST PODCI FAQ PEDSQL PRS COPM VABS CAPE KIDSCREEN MAULF SDQ WEEFIM 0

3

1

0

0

0

1

0

0

5

2

0

0

0

1

0

3

4

0

0

0

0

0

0

2

0

0

0

1

0

0 22 0 0 0

4 24 16 2 1

2 7 4 1 3

0 2 0 0 0

0 21 3 1 1

0 15 0 0 0

0 3 1 1 1

0 0 0 0 0

0 5 5 4 0

7 9 9 1 5

0 3 0 5 0

0 0 0 0 3

0 4 0 0 0

0 0 0 2 5

3 5 7 0 1

0 0

4 1

2 3

0 0

1 4

0 0

1 1

0 0

9 7

4 2

4 9

0 0

0 0

2 1

0 0

GMFM PEDI CHQ QUEST PODCI FAQ PEDSQL PRS COPM VABS CAPE KIDSCREEN MAULF SDQ WEEFIM 0

1

0

0

1

0

0

0

0

0

0

1

0

0

0

0 0

0 1

0 2

0 0

1 2

0 0

0 1

0 0

0 0

0 0

0 0

0 0

0 0

0 0

0 0

0 0

0 0

1 1

0 0

1 0

0 0

1 1

0 0

0 0

0 1

0 0

1 0

0 0

1 0

0 0

a

Complete list of multiple-item measures provided in Appendix 4 Part 2. ICF-CY; International Classification of Functioning Children and Youth version. CAPE, Children’s Assessment of Participation and Enjoyment; CHQ, Child Health Questionnaire; COPM, Canadian Occupational Performance Measure; FAQ, Gillette Functional Assessment Questionnaire; GMFM, Gross Motor Function Measure; MAULF, Melbourne Assessment of Upper Limb Function; PEDI, Pediatric Evaluation of Disability Inventory, PEDQOL, The Pediatric Quality of Life Inventory; PODCI, Pediatric Outcomes Data Collection Inventory; PRS, Physician’s rating scale; QUEST, Quality of Upper Extremity Skills Test; SDQ, Strength and Difficulties Questionnaire; VABS, Vineland Adaptive Behavior Scales.

A5LXXVIII with more detailed information for the ICF-CY content found in each measure are available as supporting information published online (Appendix 5). These tables show the specific ICF-CY codes found in each multiple-item measure. This supplementary material provides a more in depth description of the measures’ content useful for selecting a measure for clinical purposes or for research studies.

3.3. Most frequently covered areas of functioning: ICFCY categories We identified 238 outcome measures (78 multiple-item and 160 single-item measures) which contained 2193 concepts. Overall, the content of the outcome measures covered 161 independent ICF-CY categories. Out of the 161 categories, 53

8

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(33.5%) were related to body functions, 75 (46%) were related to activities and participation, 26 (16.1%) were related to environmental factors, and 7 (4.3%) were related to body structures. Table 4 shows the most relevant areas of functioning included in studies with children with CP. ICF-CY categories related to different aspects of mobility (included in chapter d4, activity and participation) were the most frequent areas of functioning addressed in the literature. Follow by neuromuscular related areas (included in chapter b7, body functions). Contextual factors representing children’s personal characteristics (personal factors), support and relationships (chapter e3) and aspects of health services (chapter e5) were also frequently included in studies in this population. A complete list of all the areas of functioning identified in this review is available in Appendix 6 (supporting information online).

4.

Discussion

4.1. CP

Content comparison of outcome measures used in

Our findings show that current outcome measures in the field of CP primarily focus on assessing the body functions and activity and participation components of the ICF-CY. The environmental factor component is less frequently considered. The body structures and personal factors components are rarely measured. These findings suggest a lack of good representation of the important interactions of the environment (physical, emotional, economic) surrounding the child as well as the child’s personal characteristics (motivation, perseverance, personality) with the child’s functional status, as these contextual factors are not often assessed in many of the measures used. Our results show that some multiple-item measures have been broadly applied in studies with children with CP, such as the GMFM, PEDI, and the CHQ. Interestingly, when we compared the content of these outcome measures, they overlapped in some ICF-CY components, mainly body functions and activity and participation, but none fully represent all the ICF-CY components. The GMFM was the most widely used outcome measure in CP, reflecting the interest in studying motor function, the defining characteristic of CP. The GMFM is the gold standard tool for assessing gross motor function in children with CP30 and as such, the linking of the GMFM mapped onto the components of body functions and activity and participation. CP is a heterogeneous condition with varying clinical presentations and potential impairments.1 This diversity is likely reflective of the array of measures used in studies among children with CP. The ICF-CY contents of the measures we found in the literature reflect the breadth of CP in the research and clinical settings. The ICF-CY categories identified by this review represent the scope of “what” areas of functioning have been the focus of study in children with CP. Our findings provide a detailed ICF-CY content analysis allowing clinicians and researchers to match the outcome measures to their intended purpose.

Consistent with the literature, the list of outcome measures identified by our review covered most of the measures described in the work of Vargus-Adams et al.36 These authors identified health professionals’ choices of outcome measures for evaluating response to an intervention in children with CP. As described by the authors, health professionals highly recommended the GMFM as the first choice and also identified an extensive list of other measures. The current study not only identifies the choices of measures in CP but also provides novel information on how to characterize each measure based on the ICF language. For single-item measures, there was a predominant selection of mobility of joints, spasticity and gait pattern as the main focus of study. The majority of these single-item measures covered the component body functions (see Appendix 3). Overall, our results showed that a comprehensive approach in terms of the ICF-CY has not always been considered by researchers who designed studies with children with CP.

4.2. CP

Selecting the most appropriate outcome measure for

The selection of an appropriate outcome measure depends on many factors including the research question, the type of intervention, the instrument’s content and psychometric properties and the availability of a version for the patient/ proxy and specific age. Previous reviews have compared the characteristics of outcome measures used in CP, providing useful information on the psychometrics properties and theoretical backgrounds of a range of instruments.37e40 Nowadays, clinicians and researchers need also to consider what areas of functioning, health and disability they are seeking to study, and to pay attention to the specific goals of the child and the child’s family. Our results may guide professionals identify the outcome measures that best matches their particular study and/or clinical purpose in relation to the ICF-CY. For example, if clinicians or researchers seek to study the component of activity and participation, specifically aspects of “mobility” (chapter d4), they might choose between the GMFM and the Gillette Functional Assessment Questionnaire (FAQ).41 In contrast, if professionals would like to include in their studies several areas of the component of activity and participation, they might choose between the PEDI, the CHQ and/or PODCI (Table 3). From our findings, no measure alone fully represents the ICF-CY; therefore a combination of measures seems most appropriate if the goal is to capture all components of the ICFCY. Based on the content analysis by our team, a possible combination of measures covering all components of the ICFCY would be the GMFM and/or the PEDI, plus the PODCI and the CPQOL. The first two measures primarily cover the components of body functions and activity and participation and thus represent different chapters within those components, while the PODCI and the CPQOL complement the previous two by covering the contextual factors (environmental and personal factors). These measures have good psychometric properties for measuring the health of children with CP.30,42 Moreover, the GMFM30 and the CPQOL34 are CP conditionspecific measures, which focus on domains of interests or

9

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Table 4 e Relevant areas of functioning represented in the studies. ICF-CY categories (code and name of categories) Body functions b760 Control of voluntary movement functions b7101 Mobility of several joints b735 Muscle tone functions b7611 Specific spontaneous movements b152 Emotional functions b1521 Regulation of emotion b770 Gait pattern functions b710 Mobility of joint functions b280 Sensation of pain b1300 Energy level Activities and Participation d450 Walking d4551 Climbing d4552 Running d4104 Standing d4103 Sitting d4500 Walking short distances d4153 Maintaining a sitting position d4550 Crawling d4452 Reaching d410 Changing basic body position d4155 Maintaining head position d4105 Bending d820 School education d4154 Maintaining a standing position d4106 Shifting the body’s centre of gravity d415 Maintaining a body position d4351 Kicking d4553 Jumping d4100 Lying down d4101 Squatting d4102 Kneeling d4107 Rolling over d4152 Maintaining a kneeling position d550 Eating d640 Doing housework d420 Transferring oneself d530 Toileting d710 Basic interpersonal interactions d4300 Lifting d4402 Manipulating d465 Moving around using equipment d920 Recreation and leisure d9201 Sports d4401 Grasping d4602 Moving around outside the home and other buildings d5101 Washing whole body d880 Engagement in play d455 Moving around d5400 Putting on clothes d6 Domestic life d460 Moving around in different locations d3 Communication d330 Speaking d9205 Socializing d440 Fine hand use d860 Basic economic transactions d445 Hand and arm use d5100 Washing body parts d560 Drinking

Frequency of representation in studies

% of studies applying the categories (>80th percentile) n ¼ 231a

148 92 92 92 68 63 56 55 53 47

64.1 (>95th percentile) 39.8 39.8 39.8 29.4 27.3 24.2 23.8 22.9 20.3

184 179 155 151 148 144 141 139 134 130 127 123 109 105 102 102 102 102 95 92 92 92 92 92 92 85 78 77 76 75 64 64 60 59 59

79.7 (>99th percentile) 77.5 (>99th percentile) 67.1 (>99th percentile) 65.4 64.1 62.3 61.0 60.2 58.0 56.3 55.0 53.2 47.2 45.5 44.2 44.2 44.2 44.2 41.1 39.8 39.8 39.8 39.8 39.8 39.8 36.8 33.8 33.3 32.9 32.5 27.7 27.7 26.0 25.5 25.5

58 57 56 56 56 55 54 54 54 51 51 50 49 49

25.1 24.7 24.2 24.2 24.2 23.8 23.4 23.4 23.4 22.1 22.1 21.6 21.2 21.2 (continued on next page)

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Table 4 e (continued ) ICF-CY categories (code and name of categories)

Frequency of representation in studies

d571 Looking after one’s safety d4 Mobility d4200 Transferring oneself while sitting d4600 Moving around within the home d5202 Caring for hair d8803 Shared cooperative play d4301 Carrying in the hands Environmental factors e3 Support and relationships e5800 Health services Personal factors pf Personal factors

% of studies applying the categories (>80th percentile) n ¼ 231a

49 48 48 48 48 48 47

21.2 20.8 20.8 20.8 20.8 20.8 20.3

55 47

23.8 20.3

65

28.1

a

Only categories represented in >20% (>80th percentile) of the studies are shown in the table. Further distribution of percentages: >24% (>85th percentile), >30% (90th percentile), >45% (95th percentile), >66% (99th percentile).

importance affected by CP. Used independently, these measures would only provide partial information on the functional profile of a child with CP. Importantly, as the ICF-CY promotes client/familycentered care, professionals must also include measures that respond to the engagement of families and children in goal settings, for example by adding the Canadian Occupational Performance Measure (COPM)43 and/or the GAS. Previous studies have shown the benefits of the application of these measures in CP.44,45 We described what areas of functioning have been of particular interest for the research community. A wide variety of areas included in the component activity and participation addressing mobility (d4), self-care (d5), and community life (d9) have been frequently identified as relevant areas of study in this population. As expected, body functions related to neuromuscular related areas were also studied. The findings in this study highlight the need for comprehensive ICF-CY based outcome measures for children with CP, encouraging a more universal approach that goes beyond impairments in body structures and body functions. Few ICFbased measures have been developed at this point in time, including the areas of activity limitation and participation restriction questionnaire (IMPACT-S),46 the parent-report measure of the participation and environment of children and youth (PEM-CY),47 a clinical measure of functioning in ankylosing spondylitis48 and the WHO Disability Assessment Schedule (WHODAS 2.0).49 Interestingly, the PEM-CY47 examines characteristics of participation in typical activities at home, school or community and perceived supports and barriers to participation in those settings, providing an excellent example on how to incorporate the component environmental factors in an outcome measure. Finally, we found that some ICF-CY categories were not specific enough to fully represent the unique content of some items. For example items addressing different “degrees of lifting” were linked to a more generic category “d4300-lifting” showing that the ICF-CY lacks the specificity described by those items. In addition, items addressing emotional functions (sadness, happiness, anger), were also linked to a broad category “b152-emotional functions” failing to keep the

detailed information provided by the items. This linking exercise could provide new information to improve the representativeness of the ICF-CY.

4.3.

Towards the ICF-CY Core Sets for CP

Developing ICF Core Sets facilitate the description of functioning in research and clinical practice by providing lists of categories that are relevant for specific health conditions.12 The development of ICF Core Sets uses an evidence-based methodology to identify the most relevant ICF categories from the entire classification system. Following the methodology endorsed by WHO for ICF Core Sets development,12 this systematic review is one of the preparatory phase studies in the development of the ICF-CY Core Sets for children with CP. The findings of this review describe what areas of functioning researchers consider to be relevant to study in children with CP. The final ICF-CY Core Sets will facilitate the systematic approach to functional assessment of children with CP. The Core Sets will also facilitate multidisciplinary collaboration encouraging all team members to use the same language “the ICF-CY categories” when describing functioning in children with CP. As mentioned above, appropriate assessment tools need to be selected to ensure coverage of the categories included in the Core Sets.

4.4.

Limitations

The findings of this study should be interpreted in light of its limitations. Firstly, we were not able to retrieve all the outcome measures described in the studies. However, we linked the majority (82%) of the measures, including the most frequently used, which provide a good representation of the overall content of outcome measures used in CP. Secondly, we included only measures that were in English, which might have under-represented the scope of outcome measures used worldwide. However, as many measures excluded due to “language other than English” were adaptations of original English versions and these were included, our results capture the vast majority of the measures used in this population.

e u r o p e a n j o u r n a l o f p a e d i a t r i c n e u r o l o g y 1 8 ( 2 0 1 4 ) 1 e1 2

5.

Conclusions

In summary, we conducted a systematic content analysis of outcome measures used in studies with children with CP. Our review found great diversity in the ICF-CY contents of the outcome measures used in this population which indicates the complexity of CP. The comparison of measures provides novel information with respect to the breadth and precision of their coverage of specific concepts, useful when planning and selecting outcomes measures for future studies.

Author contribution VS: study design; data collection; linking exercise, analysis and interpretation of the data; statistical analysis; writing-up of manuscript; intellectual content of manuscript. AK: study design, data collection, interpretation of the data, intellectual content and critical revision of manuscript. AC: study design, data analysis, interpretation of the data; intellectual content and critical revision of manuscript. KS: data collection, linking exercise and critical review of the manuscript. LM: interpretation of the data, intellectual content and critical revision of manuscript. MO: study design, interpretation of the data, intellectual content and critical reviews of the manuscript. RA: study design, intellectual content and critical revision of manuscript, mentorship of the project.

Conflict of interest The authors have stated that they had no interests which might be perceived as posing a conflict or bias.

Acknowledgment Veronica Schiariti is the recipient of a Canadian Institutes of Health Research Doctoral Research Award and salary support from the Sunny Hill Foundation for Children through a grant from the British Columbia Ministry of Education. Anne Klassen holds a Canadian Institutes of Health Research mid-career award. We express our thanks to Jane Shen for her administrative support and technical assistance in data processing. This project was conducted under the auspices of the ICF Research Branch, a cooperation partner of the WHO-FIC Collaborating Centre in Germany (at DIMDI).

Appendix A. Supplementary data Supplementary data related to this article can be found at http://dx.doi.org/10.1016/j.ejpn.2013.08.001.

11

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