Linking osteoarthritis-specific health-status measures to the International Classification of Functioning, Disability, and Health (ICF)

Measurement properties of the short version of the Western Ontario and McMaster Universities Arthritis Index (WOMAC) for individuals with knee osteoarthritis

BACKGROUND

Assessment instruments play an essential role in the management of knee osteoarthritis. This study aimed to verify the clinimetric properties and validate the short version of WOMAC's (SV-WOMAC) knee with two domains, pain (four items) and physical function (eight items) in individuals with knee osteoarthritis (KO).

METHODS

Reliability and internal consistency Construct, criterion validity, Ceiling, and floor effects analyses were performed. In addition to the SV-WOMAC, the following instruments were used: the numerical rating scale (NRPS), International Knee Documentation Committee (IKDC), the Short Form Health Survey (SF-36), and WOMAC's original version. Spearman's correlation coefficient (rho) was used to determine the magnitude of the correlation between the AFAQ and the other instruments. Moreover, the test-retest reliability and internal consistency were assessed using the intraclass correlation coefficient (ICC) and Cronbach's alpha, respectively. In addition, standard error of measurement (SEM) and minimum detectable change (MDC) were calculated.

RESULTS

One hundred and thirteen subjects with KO were included for validity analysis, and a subsample of 53 subjects was used for test-retest reliability. Adequate reliability and internal consistency were observed with ICC ≥ 0.76, SEM ≤ 1.85, MDC ≥ 5.1, and Cronbach's alpha ≥ 0.84. Regarding construct validity, correlations greater than 0.50 were observed with the IKDC, NRPS, and functional domains of the SF-36. The SV-WOMAC showed a correlation > 0.70 with the original version and did not show ceiling and floor effects.

CONCLUSION

The SV-WOMAC knee has adequate measurement properties to analyze pain and physical function in Brazilian individuals with KO.

Development and Validation of a New Patient-Reported Outcome Measure in the Arabic Language for Patients with Knee Osteoarthritis in Saudi Arabia

PURPOSE

In Western countries, several patient-reported outcomes (PROs) measures have been developed and validated for knee osteoarthritis (OA) patients. While few PROs have been adopted for these patients in Saudi Arabia, which do not reflect all aspects of the Saudi socio-cultural context. Given this shortcoming, this study aimed to develop a new PRO measure in Arabic that covers all concepts related to health, function, and participation encompassing environmental and personal factors.

PATIENTS AND METHODS

A cross-sectional study was conducted on 73 males and females aged ≥55 diagnosed with radiographic knee OA recruited from the orthopedic and physiotherapy departments of five hospitals in Riyadh, Saudi Arabia, between September 2016 and March 2017. Physicians confirmed knee OA according to the American College of Rheumatology standards. We examined the psychometric properties of the new Arabic PRO measure.

RESULTS

The internal consistency and test-retest (a one-week interval) reliabilities were found acceptable and excellent with Cronbach's alpha and the intra-class correlation coefficient, ranging from 0.69 to 0.85 and 0.88 to 0.91, respectively. The construct validity was found fair with the correlation between the subscales Body Function and Physical Function (rs =0.63), Activity & Participation and Physical Function (rs =0.72), and Body Function and Bodily Pain (rs =0.58). We found a weak to fair correlation between the new Arabic PRO measure's subscales and the SF-36 physical composite scale (PCS: rs =0.34-0.69) compared to the mental-composite scale (MCS: rs =0.16-0.55).

CONCLUSION

The 33-item new Arabic PRO measure is a well-accepted, reliable, and valid tool for use in knee OA patients in the Saudi cultural context.

From individualised treatment goals to personalised rehabilitation in osteoarthritis: a longitudinal prospective mapping study using the WHO international classification for functioning, disability and health

BACKGROUND/OBJECTIVE(S)/INTRODUCTION

In clinical practice, treatment goals are often set up without exploring what patients really want. We, therefore, collected individualised treatment goals of patients with osteoarthritis (OA), categorised and mapped them to the World Health Organisation International Classification for Functioning, Disability and Health (ICF).

PATIENTS/MATERIALS AND METHODS

A longitudinal prospective cohort study was conducted (2019-2021). We used descriptive statistics and Chi²/Fisher's Exact Tests, where appropriate, as well as Kruskal-Wallis-Tests for the mean score ranks of the patients' goals.

RESULTS

In total, 305 goals reported by 132 participants were analysed (267 women vs. 38 men). The top 3 ICF categories were sensation of pain (ICF:b280), mobility of joint (ICF:b710) and muscle power functions (ICF:b730). Overall, 51% of all individually reported functional goals were achieved after 3 months. Men were more likely to achieve their goals than women (p = 0.009). The majority of the "very important" goals (51%) and "very difficult" goals (57%) was not improved. Goals' mean score ranks significantly differed between baseline and follow-up.

CONCLUSION(S)

As the human lifespan as well as the number of people affected by OA worldwide increase, there is a growing need to identify and evaluate rehabilitation outcomes that are relevant to people with OA.Key MessagesTreat-to-target agreements between patients and health care providers present a step towards more personalised precision medicine, which will eventually lead to better reported functional and health outcomes.In patients with osteoarthritis, the Goal Attainment Scale instrument can be used to measure health outcomes at different time points and its content may be linked to ICF providing a unified language and conceptual scientific basis.

Behavioural and patient-individual determinants of quality of life, functioning and physical activity in older adults (MobilE-TRA 2): study protocol of an observational cohort study in a tertiary care setting

INTRODUCTION

Vertigo, dizziness and balance problems (VDB) as well as osteoarthritis (OA) are among the health conditions with the greatest impact on mobility and social participation in older adults. Patients with VDB and OA were shown to benefit from specialised care such as vestibular rehabilitation therapy or joint replacement. However, these effects are not permanent and seem to disappear over time. One important reason might be a decreasing adherence to therapy recommendations. Findings from behavioural economics (BE) can help to shed light on individual effects on adherence behaviour and long-term outcomes of VDB and OA.

OBJECTIVE

Based on insights from BE concepts (ie, self-efficacy, intention, and time and risk preferences), MobilE-TRA 2 investigates the determinants of functioning and health-related quality of life (HRQoL) 3 and 12 months after discharge from total hip replacement (THR)/total knee replacement (TKR) in patients with OA and after interdisciplinary evaluation for VDB.

METHODS AND ANALYSIS

MobilE-TRA 2 is a longitudinal observational study with data collection in two specialised tertiary care centres at the university hospital in Munich, Germany between 2020 and 2023. Patients aged 60 and older presenting for their first THR/TKR or interdisciplinary evaluation of VDB at Ludwig Maximilians University (LMU) hospital will be recruited for study participation. Three and twelve months after baseline assessment, all patients will receive a follow-up questionnaire. Mixed-effect regression models will be used to examine BE concepts as determinants of adherence, HRQoL and functioning.

ETHICS AND DISSEMINATION

The study was approved by the ethics committee at the medical faculty of the LMU Munich under the number 20-727. Results will be published in scientific, peer-reviewed journals and at national and international conferences. Findings will also be disseminated via newsletters, the project website and a regional conference for representatives of local and national authorities.

The Patient-Rated Elbow Evaluation and the American Shoulder and Elbow Surgeons-Elbow form capture aspects of functioning that are important to patients with elbow injuries

STUDY DESIGN

This is a cross-sectional study.

INTRODUCTION

The Patient-Rated Elbow Evaluation (PREE) and the self-report section of the American Shoulder Elbow Surgeons-elbow form (pASES-e) are two important elbow-specific self-report measures used in routine clinical practice.

PURPOSE OF THE STUDY

To use the International Classification of Functioning Disability and Health (ICF) to link aspects of functioning that are reported using the Patient-Specific Functional Scale by a cohort of patients with elbow disorders and compare it to the content of the PREE and the pASES-e.

METHODS

One hundred patients with a variety of elbow disorders (mean age and SD 53.88 (14.51); M: F 48: 52) were recruited from the Roth-McFarlane Hand and Upper Limb Centre. They self-reported important aspects of functioning using the Patient-Specific Functional Scale. These concerns were linked to the ICF using formal linking procedures. These ICF categories were compared to the categories related to the PREE and the pASES-e. Linking was carried out by two independent raters, and agreement was calculated using percentage agreement.

RESULTS

A total of 423 self-reported functional activities were linked to 25 second-level ICF categories from the activity and participation domain. Commonly reported activities were D640 doing housework (52%); D540 dressing (47%); and D475 driving (35%). PREE had better coverage of the patient concerns (71%) than pASES-e (50%). D475-driving (35%) and D440-fine hand use (24%) were the 2 major categories that were not captured by the questionnaires. Agreement between the raters was 90.5%.

DISCUSSION

This study established that the PREE and the pASES-e were able to capture aspects of functioning important to patients and that align with the ICF, with this happening to a greater extent on the PREE than the pASES-e. Because all patients reported concerns from the activity and participation section ('d' categories) of the ICF, this validated that these PROMs measure this conceptual domain.

CONCLUSION

The PREE provided more comprehensive coverage of patients' functional concerns than the pASES-e.

ICF Linking and Cognitive Interviewing Are Complementary Methods for Optimizing Content Validity of Outcome Measures: An Integrated Methods Review

Content validity is a fundamental requirement of outcome measures. After reviewing operational needs and existing definitions, content validity we as defined as: the extent to which a measure provides a comprehensive and true assessment of the key relevant elements of a specified construct or attribute across a defined range, clearly and equitably for a stated target audience and context. ICF linkage rules from 2002, 2005, and 2019 have provide increasingly clear processes for describing and evaluating content of outcome measures. ICF Core Sets provide international reference standards of the core constructs of importance for different health conditions. Both are important as reference standards during content validation. To summarize their use as reference standards, the following summary indicators were proposed: (1) Measure to ICF linkage, (2) Measure to (Brief or Comprehensive) Core Set Absolute Linkage, (3) Measure to (Brief or Comprehensive) Core Set Unique Linkage, (4) Core Set Representation, and (5) Core Set Unique Disability Representation. Methods to assess how respondents engage with content are needed to complement ICF-linking. Cognitive interviewing is an ideal method since it used to explore how respondents interpret and calibrate response to individual items on an outcome measure. We proposed a framework for classifying these responses: Clarity/Comprehension, Relevance, Inadequate response definition, Reference Point, Perspective modification, and Calibration Across Items. Our analysis of 24 manuscripts that used ICF linking for content validation since updated linking rules were published found that authors typically used linking to validate existing measures, involved multiple raters, used 2005 linking rules, summarized content at a concept level (e.g., impairment, activity, participation) and/or use core sets as a reference standard. Infrequently, ICF linking was used to create item pools/conceptual frameworks for new measures, applied the full scope of the 2019 linking rules, used summary indicators, or integrated ICF-linking with qualitative methods like cognitive interviews. We conclude that ICF linkage is a powerful tool for content validity during development or validation of PROM. Best practices include use of updated ICF linking rules, triangulation of ICF linking with participant assessments of clarity and relevance preferably obtained using cognitive interview methods, and application of defined summary indicators.

Development International Classification of Functioning, Disability and Health Core Set for Post Total Knee Replacement Rehabilitation Program: Delphi-Based Consensus Study in Taiwan

Osteoarthritis is one of the leading causes of disability. Total knee arthroplasty (TKA) is a surgical intervention for patients with severe osteoarthritis. Post TKA rehabilitation is crucial for improving patient's quality of life. However, traditional rehabilitation has only focused on physical function; a systemic analysis of other dimensions such as social participation and environmental factors of post TKA rehabilitation is lacking. The aim of this study was to develop a core set from the International Classification of Functioning, Disability and Health (ICF) to create a comprehensive rehabilitation program for patients with osteoarthritis post TKA. Before the Delphi-based consensus process, a literature review process was performed for related ICF categories selection. We used a three-round Delphi-based consensus among 20 physical therapists with orthopedic rehabilitation expertise in a university-based hospital. A five-point Likert scale was used to rate the importance of each item. The consensus of ratings was analyzed using Spearman's rho and semi-interquartile range indices. The ICF core set for post TKA rehabilitation was determined based on a high level of consensus and a mean score of ≥4.0 in the third Delphi-based consensus round. The ICF core set comprised 32 categories, with 13 regarding body function, four regarding body structures, nine regarding activities and participation, four regarding environmental factors, and two regarding personal factors. Our ICF core set for post TKA rehabilitation can provide information on effective rehabilitation strategies and goal setting for patients post TKA. However, further validation and feasibility assessments are warranted.

Instrumentos da prática clínica com versão em português e a abrangência de seus conteúdos usando a CIF como referência: uma revisão sistemática

RESUMO A prática clínica tem sido subsidiada por instrumentos que permitem acessar e registrar informações de funcionalidade e saúde dos indivíduos. Uma forma de conhecer qual conteúdo da Classificação Internacional de Funcionalidade, Incapacidade e Saúde (CIF) os instrumentos contemplam é usá-la como referência para auxiliar o profissional na escolha do mais adequado para acessar informações biopsicossociais. O objetivo foi identificar instrumentos da prática clínica em saúde que tiveram seu conteúdo ligado com a CIF e a existência de versão na língua portuguesa deles. Para tanto foi realizada uma revisão sistemática nas bases de dados SciELO Brasil, Lilacs e PubMed com os descritores “CIF”, “questionário” e “regra de ligação” em português e inglês. Três pesquisadores independentes realizaram a seleção, e o nível de concordância foi obtido pelo coeficiente Kappa. Os critérios de elegibilidade foram: estudos primários de ligação de conteúdo de questionários, escalas, índices e checklists com a CIF publicados após 2001 em língua portuguesa ou inglesa. Foram incluídos 61 artigos, sendo 19 de origem brasileira. Dos 250 instrumentos ligados à CIF, 158 (63,2%) apresentaram versão em português sendo que dos 37 que mais se repetiram nos estudos, dois não apresentam essa versão. O coeficiente Kappa mostrou concordância entre moderada e boa (p<0,001). Este estudo apresentou um panorama da ligação de conteúdo de instrumentos da prática clínica à CIF identificando quais têm versão em língua portuguesa, o que contribuirá para o potencial fortalecimento da abordagem biopsicossocial dos profissionais de saúde.

Investigation of the relationship between quality of life, activity participation and environmental factors in adolescents with cerebral palsy

BACKGROUND AND OBJECTIVE

The aim of this study is to examine the relationship between quality of life, activity-participation and environmental factors in adolescents with cerebral palsy.

METHODS

Seventy-five (75) adolescents (M:45, F:30) aged between 14-18 years (mean: 15.52±1.60 yrs) were included in the study. Participants were divided into three groups: Level I, Level II and Level III according to the Gross Motor Function Classification System. Gross Motor Function Classification System, Gross Motor Function Measure, Functional Independence Scale, Manual Ability Classification System, Pediatric Quality of Life Inventory and International Classification of Functioning, Disability and Health Child-Youth version Short Form (ICF-CY) (14-18 yrs) were used for assessments.

RESULTS

It is found that there is a moderate and high level of correlation between quality of life and activity participation and body functions, a moderate and high level of correlation between quality of life and activity participation and body functions with gross motor function levels, and a moderate and low level correlation between environmental factors and gross motor function levels (p < 0.05).

CONCLUSIONS

The fact that the ICF-CY short form used for cerebral palsied children is compatible with other assessment scales suggests that the use of ICF-CY short forms may be useful in assessing the health status of individuals.

Development of an extensive assessment list for knee osteoarthritis based on the International Classification of Functioning, Disability and Health: a Delphi study

The objective of this study was to develop an extensive assessment list for individuals with knee osteoarthritis based on the International Classification of Functioning, Disability and Health (ICF) osteoarthritis comprehensive Core Set. Ten experienced physical therapists including five lecturers and five clinicians were purposively nominated to form an expert panel. Consensus among the experts was obtained through a four-iteration Delphi technique. A list of ICF categories and their third- and fourth-level categories were selected and matched with outcome measures associated with knee osteoarthritis. The expert panel agreed that 26 out of 38 second-level categories of the comprehensive ICF core set for osteoarthritis were relevant to identify problems related to knee osteoarthritis. The information relevant to the specific categories for knee osteoarthritis was obtained from self-reported, subjective observation and physical examination. The extensive assessment list for knee osteoarthritis based on the comprehensive ICF core set for osteoarthritis was assembled. This assessment tool can be used to expansively identify the multidimensional disabilities of impairment, activity limitation and participation restriction in individuals with knee osteoarthritis.

The content comparison of health-related quality of life measures in heart failure based on the international classification of functioning, disability, and health: a systematic review

Introduction: Due to the necessity of assessing the health-related quality of life (HRQOL) in heart failure (HF) and the increased use of the International Classification of Functioning, Disability, and Health (ICF) for making a content comparison of measurement instruments, the present study aimed to evaluate the relationship between the instruments and ICF. To this aim, the disease-specific HRQOL instruments in HF were identified, and then psychometric properties and content comparison of included instruments were conducted by linking to ICF. Methods: Disease-specific HRQOL instruments in HF were identified through a comprehensive and systematic search strategy. Then, the psychometric properties of included instruments were determined, and their contents were analyzed and compared based on the ICF coding system. In addition, each instrument was independently linked to ICF by two researchers based on standardized linking rules, and finally their degree of agreement was assessed by the Cohen's kappa coefficient. Results: Ten instruments including a total of 247 items and 417 concepts were linked to 124 different ICF categories. Further, 39 (31.5%), 65 (52.5%), 13 (10.4%), and 7 (5.6%) categories were linked to body function, activity and participation, environmental factors, and body structure, respectively. According to the content analysis approach and psychometric properties, the appropriate measurement instruments were Kansas City Cardiomyopathy and Minnesota living with HF questionnaires, respectively. Conclusion: Content comparison provides researchers with valuable information on the instrument heterogeneity and overlapping, which results in selecting the most appropriate measurement instrument based on a specific clinical context.

Investigation of the relationship between quality of life, activity-participation and environmental factors in adolescents with cerebral palsy

BACKGROUND AND OBJECTIVE

The aim of this study is to examine the relationship between quality of life, activity-participation and environmental factors in adolescents with cerebral palsy.

METHODS

Seventy-five adolescents (M:45, F:30) ages between 14-18 yrs (mean: 15.52±1.60 yrs) were included in the study. Participants were divided into three groups: Level I, Level II and Level III according to the Gross Motor Function Classification System. Gross Motor Function Classification System, Gross Motor Function Measure, Functional Independence Scale, Manuel Ability Classification System, Pediatric Quality of Life Inventory and International Classification of Functioning, Disability and Health Child-Youth version Short Form (ICF-CY) (14-18 yrs) were used for assessments.

RESULTS

It is found that there is a moderate and high level of correlation between quality of life and activity participation and body functions; moderate and high level of correlation between quality of life and activity participation and body functions with the gross motor function levels; moderate and low level correlation between environmental factors and gross motor function levels (p < 0,05).

CONCLUSIONS

The fact that the ICF-CY short form used for cerebral palsied children is compatible with other assessment scales suggests that the use of ICF-CY short forms may be useful in assessing the health status of individuals.

Evaluation of a Cost-Effective Novel Diagnostic Method for Lumbar Herniated Disc with Knee-Osteoarthritis: A Randomized Sample Study

The aim of this study was to determine a cost-effective diagnostic method for lumbar herniated disc with knee osteoarthritis (LHD-KOA) based on aberrant outcome measures, levels of biomarkers, and examination of the lower-extremity. Data were separately analyzed for each cohort suffering with LHD-KOA (n=108; 59.82±7.15years) and without LHD-KOA (n=108; 58.81±7.61years), and findings were confirmed with radiological images. The aberrant-leg-features (bilateral: knee gaps between the short head of biceps femoris and the surface of the bed, diameters of calves and thighs, angles of straight leg raising, knee-flexion and -extension in a supine position) and biochemical parameters (Interleukin-10, Tumor necrosis factor-alpha, C-reactive protein, creatine kinase-muscle, and Aldolase-A), and outcome measures, Western Ontario and McMaster Universities osteoarthritis index (WOMAC), knee-injury osteoarthritis outcomes scale (KOOS), Oswestry disability index (ODI), and body mass index (BMI)for participants with and without LHD-KOA were evaluated with appropriate techniques. All the subjects underwent standardized physical examination and completed a questionnaire. The risk ratios and mean± standard deviations of biomarkers, anatomical features, and outcome measures of the experimental subjects were highly significant compared to controls (p<0.0001). Results suggest that monitoring the studied aberrant outcome measures, biomarkers, and lower-anatomical features may be a cost-effective diagnostic tool for LHD-KOA. Further research is recommended for an alternative treatment protocol for LHD-KOA.

Exploring the relation between impairment rating by DAS-28 and body function, activity participation, and environmental factors based on ICF hand core set in the patient with rheumatoid arthritis

Hand problems associated with rheumatoid arthritis lead to subjective impairment, activity limitation, and restrictions on participation. This relation is very complex. Assessment of individuals' activities is important to determine how hand problems affect not only body functions but also daily life activities. The aim of this study was to link and allocate items of disability questionnaires with ICF components based on ICF hand core set. The other objective was to examine the relationship between impairment and ICF components determined on the basis of disability questionnaires in participants with rheumatoid arthritis. Impairment was evaluated by use of Disease Activity Score-28. Disability questionnaires were Disabilities of Arm, Shoulder and Hand Questionnaire, Michigan Hand Outcomes Questionnaire, Duruoz Hand Index, and Arthritis Impact Measurement Scales 2 (n = 100). Items of disability questionnaires were linked with ICF hand core set as a result of three expert opinions. Michigan Hand Outcomes Questionnaire covered the highest number of body function categories and Arthritis Impact Measurement Scales 2 covered the highest number of ICF hand core set. For all questionnaires, while impairment (Disease Activity Score-28) had moderate correlation with subjective impairment (body function scores) and activity/participation; subjective impairment had high and moderate correlation with activity participation. Arthritis Impact Measurement Scale 2 is the most appropriate to perform a more comprehensive biopsychosocial assessment. Clinician's assessments and impairment levels reported by patients with rheumatoid arthritis are interrelated. Impairment levels reported by patients with rheumatoid arthritis are also affected by environmental factors.

Content comparison of guideline-recommended instruments used in treatment for alcohol use disorders

PURPOSE

Practice guidelines recommend the use of standardized instruments in the treatment of alcohol use disorders (AUDs); however, the extent to which these instruments assess patients' functioning is unclear. The aim of this study was to examine the domains of functioning and contextual factors contained in guideline-recommended instruments, using the International Classification of Functioning, Disability, and Health (ICF) as a reference.

MATERIALS AND METHODS

We identified instruments by reviewing AUD treatment guidelines used in Germany, Canada, Australia and New Zealand, United Kingdom, and United States. We included instruments which were available in English free of charge, we excluded instruments developed solely for diagnostic or epidemiological purposes and those for children or adolescents. Following a standardized set of rules, two health care researchers identified the concepts contained in the items on the instruments and independently linked them to ICF categories.

RESULTS

A total of 10 instruments were included. Among 517 items, 752 meaningful concepts (MCs) were derived, and 622 of them were linked to the ICF. Inter-rater agreement was κ = 0.61. One hundred eighty eight MCs referred to personal factors, 175 to body functions, 168 to activity and participation, and 91 to environmental factors. The most frequently linked ICF chapter was b1 (mental functions).

CONCLUSIONS

Instruments recommended in AUD treatment guidelines vary considerably in their assessment of patients' functioning and contextual factors. Within the investigated instruments, environmental factors are under-represented in comparison to body functions and personal factors. ICF linkage provides guidance for clinicians and researchers in the selection of appropriate instruments. Implications for rehabilitation Since instruments that are recommended in alcohol treatment guidelines vary considerably in respect the functioning domains and context factors they cover, it may be challenging for clinicians to select instruments relevant to their treatment context. Using the ICF as framework, our results provide guidance for clinicians in how to select appropriate instruments. Within the investigated instruments, environmental factors and activities and participation are under-represented in comparison to body functions and personal factors. Clinicians may employ AUD-unspecific or ICF-based instruments to cover these components if needed.

Shoe Lifts for Leg Length Discrepancy in Adults With Common Painful Musculoskeletal Conditions: A Systematic Review of the Literature

OBJECTIVE

To determine whether shoe lifts effectively treat leg length discrepancy (LLD)-associated morbidities in adults with common painful musculoskeletal conditions.

DATA SOURCES

Trip database, Cochrane Central Register of Controlled Trials database, PubMed database, Physiotherapy Evidence Database, and National Guideline Clearinghouse database. The search was performed in September 2017, was limited to English only, and had no time constraints.

STUDY SELECTION

Two reviewers independently determined study eligibility. Inclusion criteria were (1) participants ≥18 years old with musculoskeletal-related complaints and LLD; (2) a shoe lift intervention was used; and (3) the study reported on pain, function, range of motion, patient satisfaction, quality of life, or adverse events. Randomized controlled trials (RCTs) and controlled intervention, cohort, before-and-after, case series, and case report studies were included. Three-hundred and nineteen articles were screened, and 9 guidelines were reviewed.

DATA EXTRACTION

We extracted data pertaining to participant demographic characteristics, study setting, recruitment, randomization, method of LLD measurement, shoe lift characteristics, treatment duration, and outcome measures. We included 10 studies, including 1 RCT.

DATA SYNTHESIS

LLD was associated with low back pain, scoliosis, and osteoarthritis of the hip and knee. Description of LLD correction strategy was often inadequate. Study quality was very low or poor. In non-RCT studies reporting on the proportion of participants who improved with a shoe lift, 88%±3% of 349 participants treated had partial or complete pain relief (effect size range, 66.7%-100%). All 22 RCT participants receiving treatment experienced pain relief (mean pain reduction, 27±9mm on a 150-mm visual analog scale). Two of 9 guidelines recommended shoe lift use based on consensus and were of moderate-to-high quality.

CONCLUSIONS

There is low-quality evidence that shoe lifts reduce pain and improve function in patients with LLD and common painful musculoskeletal conditions. High-quality research evaluating a threshold LLD to correct and a strategy to do so is necessary. Developing an appropriate comparison group to test clinically relevant outcome measures would make a valuable contribution in this regard.

Measuring everyday functional competence using the Rasch assessment of everyday activity limitations (REAL) item bank

OBJECTIVE

Traditional patient-reported physical function instruments often poorly differentiate patients with mild-to-moderate disability. We describe the development and psychometric evaluation of a generic item bank for measuring everyday activity limitations in outpatient populations.

STUDY DESIGN AND SETTING

Seventy-two items generated from patient interviews and mapped to the International Classification of Functioning, Disability and Health (ICF) domestic life chapter were administered to 1128 adults representative of the Dutch population. The partial credit model was fitted to the item responses and evaluated with respect to its assumptions, model fit, and differential item functioning (DIF). Measurement performance of a computerized adaptive testing (CAT) algorithm was compared with the SF-36 physical functioning scale (PF-10).

RESULTS

A final bank of 41 items was developed. All items demonstrated acceptable fit to the partial credit model and measurement invariance across age, sex, and educational level. Five- and ten-item CAT simulations were shown to have high measurement precision, which exceeded that of SF-36 physical functioning scale across the physical function continuum. Floor effects were absent for a 10-item empirical CAT simulation, and ceiling effects were low (13.5%) compared with SF-36 physical functioning (38.1%). CAT also discriminated better than SF-36 physical functioning between age groups, number of chronic conditions, and respondents with or without rheumatic conditions.

CONCLUSION

The Rasch assessment of everyday activity limitations (REAL) item bank will hopefully prove a useful instrument for assessing everyday activity limitations. T-scores obtained using derived measures can be used to benchmark physical function outcomes against the general Dutch adult population.

Linking of the American Academy of Orthopaedic Surgeons Distal Radius Fracture Clinical Practice Guidelines to the International Classification of Functioning, Disability, and Health; International Classification of Diseases; and ICF Core Sets for Hand Conditions

Background: American Academy of Orthopaedic Surgeons (AAOS) distal radius fracture (DRF) clinical practice guidelines (CPG) are readily available to clinicians, patients, and policymakers. International Classification of Functioning, Disability, and Health (ICF) provides a framework for describing the impact of health conditions. The International Classification of Diseases-10th Revision (ICD-10) is a classification system to classify health conditions as specific disease or disorders. The aim of this study is to analyze and describe the scope and focus of the AAOS DRF CPG using the ICF and ICD-10 as a basis for content analysis, and to compare the content of the CPG with the ICF hand core sets as the reference standard. Methods: Established linking rules were used by 2 independent raters to analyze the 29 recommendations of the AAOS DRF CPG. ICD-10 codes were assigned in the same process. Summary linkage statistics were used to describe the results for ICF and the hand core sets. Results: Among the 29 recommendations of the AAOS DRF CPG, 5 meaningful concepts were linked to the ICF codes. Of these, 5 codes appeared on the comprehensive ICF core set and only 3 codes appeared in the brief ICF core set, and 7 conditions were covered in ICD-10 codes. Conclusions: The AAOS DRF CPG focuses on surgical interventions and has minimal linkage to the constructs of the ICD-10 and ICF. It does not address activity or participation (disability), and is not well linked to key concepts relevant to hand conditions.

Predictors and outcome of pain-related avoidance of activities in persons with early symptomatic knee osteoarthritis: a five-year followup study

OBJECTIVE

It has been hypothesized that pain and low vitality lead to an increase in avoidance of activities in persons with early symptomatic knee osteoarthritis (OA), and that avoidance of activities leads to an increase in activity limitations. The present study aimed to evaluate these hypotheses.

METHODS

Baseline, 2-year, and 5-year followup data of 828 participants from the Cohort Hip and Cohort Knee Study with early symptomatic knee OA were used. Autoregressive generalized estimating equations and linear regression models were used to analyze the longitudinal and cross-sectional associations between self-reported knee pain, vitality, pain-related avoidance of activities, and activity limitations. The models were adjusted for the covariates age, sex, education level, body mass index, comorbidity, radiographic severity, and hip pain.

RESULTS

In longitudinal analyses, knee pain and vitality predicted a subsequent increase in avoidance of activities. Pain-related avoidance of activities predicted a subsequent increase in activity limitations; however, this relationship lost statistical significance (P = 0.089) after adjustment for covariates. Cross-sectional analyses showed strong relationships between knee pain, low vitality, pain-related avoidance of activities, and activity limitations at all time points.

CONCLUSIONS

In persons with early symptomatic knee OA, knee pain and low vitality lead to a subsequent increase in avoidance of activities. Pain-related avoidance of activities is related to activity limitations at inception of symptoms, but also years later. Therefore, it can be recommended to monitor and target avoidance of activities at various stages of the disease.

Measurement properties of the Western Ontario and McMaster Universities Osteoarthritis Index: a systematic review

OBJECTIVE

To conduct a systematic review of the measurement properties of the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) and to evaluate the quality of WOMAC measurement studies using COSMIN (Consensus-Based Standards for the Selection of Health Measurement Instruments) criteria.

METHODS

A search was conducted in the MEDLINE, CINAHL, Embase, PsycINFO, Scopus, and SPORTDiscus databases through September 2013. Data that assessed the WOMAC measurement model, reliability, validity, respondent burden, and equivalence across methods of administration were extracted. Overall study quality was rated following COSMIN criteria.

RESULTS

A total of 76 articles from 22 countries were included. Internal consistency reliability was consistently high (≥0.90) for the function scale and acceptable (≥0.70) for the pain and stiffness scales. Test-retest reliability was acceptable. Score equivalence was demonstrated across paper and electronic methods of data collection. Floor and ceiling effects were low except for notable (24-38%) proportions of patients achieving the best possible scores on the pain and stiffness scales 1-23 years after arthroplasty. Five exploratory factor analyses did not support a measurement model in which the pain and function items were distinct. Correlations between the WOMAC pain and function scales were high (median 0.79). The WOMAC pain and function scales had similar correlations with other pain measures, and therefore the WOMAC pain scale did not show divergent validity. COSMIN criteria were not fully met in most studies.

CONCLUSION

The WOMAC scales were reliable, but its pain scale was highly related to physical function. Further research into joint-specific pain measures that have broader content validity is needed.

Methodological challenges in the use of hip-specific composite outcomes: linking measurements from hip fracture trials to the International Classification of Functioning, Disability and Health Framework

INTRODUCTION

The prevalence of hip-specific outcome measures in randomized trials reflects what directs our outcome assessment following a hip fracture. The present study provides an overview on the most commonly-used hip-specific outcome instruments used for postoperative assessment of hip fracture with respect to their covered contents. This can facilitate the selection of appropriate items for specific purposes in clinical as well as research settings.

METHODS

We used the International Classification of Functioning, Disability and Health (ICF) model to distinguish concepts within the instrument. All items from the questionnaires were categorized into one of three categories using the ICF linking rules for a standardized approach. The hip-specific composites measures were also compared to other types of prevalent measures: generic and patient-based instruments.

RESULTS

All of the items in the instruments could be mapped to the ICF. We report the highest frequency of ICF activity and participation (71%) within the Harris hip score (HHS) which is similar to the frequency of ICF content found in the generic measures (82%). Hip-specific composites focused mostly on walking and moving long and short distances, while in patient-reported measures there was a concentration on the concept of sensation of pain and pain in body parts.

DISCUSSION AND CONCLUSION

The prevalent use of the HHS, over the other hip-specific instruments, could be attributed to its likeness in concept to other generic measures. The dominance of the ICF category of activity and participation reflects what is important to clinicians treating a hip fracture. Composite scores remain problematic as they cut across different ICF concepts. As long as the popularity of composite scoring systems continues, an overall score may not represent the true patient preferences and concerns in clinical trials. Future studies could apply the results from this study for the creation of an ICF category-based item banking or investigators could operationalize the ICF categories within these candidate measures for specific interventions.

Does the impact of osteoarthritis vary by age, gender and social deprivation? A community study using the International Classification of Functioning, Disability and Health

Abstract Purpose: The aim of the study was to explore if the impact of osteoarthritis varies with respect to age, gender and social deprivation. Impact was defined as impairment, activity limitations and participation restriction (International Classification of Functioning, Disability and Health (ICF)). Investigating the functioning of the ICF model for subgroups is important both practically and theoretically.

METHOD

The sample comprised a community sample of 763 people diagnosed with osteoarthritis. Uncontaminated measures of the ICF constructs were developed using discriminant content validity from a pool of 134 items, including the WOMAC and SF-36. Multigroup Structural Equation Modelling was used to explore if the same pathways exist for subgroups of gender, age and social deprivation.

RESULTS

Different significant paths were found for gender and social deprivation: impairment did not predict participation restriction for women and those most deprived, whereas these paths were significant for men and those less deprived. No difference in the paths was found for age.

CONCLUSIONS

The impact of osteoarthritis appears to vary with respect to gender and social deprivation but not age. This suggests both that osteoarthritis per se does not adequately explain the health outcomes observed and that different clinical approaches may be appropriate for people of different gender and levels of deprivation. Implications of Rehabilitation The ICF model appears to vary with respect to gender and social deprivation for people with osteoarthritis. The ICF model did not appear to vary with respect to age for people with osteoarthritis. Different treatments and interventions for osteoarthritis may need to be targeted for specific gender and social deprivation groups.

Social participation restriction among US adults with arthritis: a population-based study using the International Classification of Functioning, Disability and Health

OBJECTIVE

To examine arthritis impact among US adults with self-reported doctor-diagnosed arthritis using the International Classification of Functioning, Disability and Health (ICF) framework (including the impairments, activity limitations, environmental, and personal factors domains and social participation restriction [SPR] as the outcome) overall and among those with and without SPR, and to identify the correlates of SPR.

METHODS

Cross-sectional 2009 National Health Interview Survey data were analyzed to examine the distribution of the ICF domain components. Unadjusted and multivariable-adjusted prevalence ratios (PRs) and 95% confidence intervals (95% CIs) were estimated to identify the correlates of SPR. Analyses using SAS, version 9.2 survey procedures accounted for the complex sample design.

RESULTS

SPR prevalence was 11% of adults with arthritis (5.7 million). After initial multivariable adjustment by ICF domain, serious psychological distress (impairments domain; PR 2.5 [95% CI 2.0-3.2]), ≥5 medical office visits (environmental domain; PR 3.4 [95% CI 2.5-4.4]), and physical inactivity (personal domain; PR 4.8 [95% CI 3.6-6.4]) were most strongly associated with SPR. A combined measure (key limitations [walking, standing, or carrying]; PR 31.2 [95% CI 22.3-43.5]) represented the activity limitations domain. After final multivariable adjustment incorporating all ICF domains simultaneously, the strongest associations with SPR were key limitations (PR 24.3 [95% CI 16.8-35.1]), ≥9 hours of sleep (PR 1.6 [95% CI 1.3-2.0]), and income-to-poverty ratio <2.00 and severe joint pain (PR 1.4 [95% CI 1.2-1.6] for both).

CONCLUSION

SPR affects 1 of 9 adults with arthritis. This study is the first to use the ICF framework in a population-based sample to identify specific functional activities, pain, sleep, and other areas as priorities for intervention to reduce negative arthritis impacts on disability, including SPR. Increased use of existing clinical and public health interventions is warranted.

Are the mental representations of people with osteoarthritis consistent with the International Classification of Functioning Disability and Health?

PURPOSE

This study examined whether the mental representations of people with osteoarthritis (OA) were consistent with the International Classification of Functioning Disability and Health (ICF) model.

METHODS

A geographical cohort of 202 people with OA about to have joint replacement surgery completed postal questionnaires. Mental representations were measured by asking participants what they were hoping for from their joint replacement. Two expert judges classified these illness representations to the main ICF constructs of Impairment (I), Activity Limitation (A) and Participation Restriction (P).

RESULTS

There was strong agreement between the expert judges. There were a similar number of illness representations for each of the ICF constructs. The primary biomedical route of the ICF model was suggested by the ordering of the participants' illness representations i.e. I to A to P.

CONCLUSIONS

The mental representations of people with OA were consistent with the ICF theoretical framework with all three ICF constructs of importance. It appeared that people with OA implicitly apply a biomedical causal model of disability, suggesting that treatments and interventions aimed at reducing impairment may only affect P indirectly, through A. Additionally, the methods provide a novel way of exploring the potential causal relationships between constructs of the ICF model.

Testing an Adapted ICF Model: Aging, Vision Impairment, Activity, Participation and Subjective Dimensions of Functioning

An adapted model of the ICF, which incorporates subjective dimensions of functioning, has proven useful in classifying variables for research. This model was tested for its potential for further development. The following study evaluates the relationships between the components of the adapted ICF model. Five hundred and sixty surveys from adults aged 65+ from the Manawatu region of New Zealand were analyzed to test the proposed model. An adapted model of the ICF, developed in prior research exploring the impact of vision impairment on the lives of older adults, was tested. There was evidence to support the proposal that the adapted ICF model is valid and that there are moderate and strong relationships between the components. Results can influence further development of the ICF and details of this study can enhance research, practice, policy and education related to aging and human service delivery. Providers, educators and researchers should be encouraged to incorporate subjective dimensions of functioning, such as satisfaction measures, into assessments related to rehabilitation of older adults.

Reliability, construct validity and measurement potential of the ICF comprehensive core set for osteoarthritis

BACKGROUND

This study aimed to investigate the reliability and construct validity of the International Classification of Functioning, Disability and Health (ICF) Comprehensive Core Set for osteoarthritis (OA) in order to test its possible use as a measuring tool for functioning.

METHODS

100 patients with OA (84 F, 16 M; mean age 63 yr) completed forms including demographic and clinical information besides the Short Form (36) Health Survey (SF-36®) and the Western Ontario and McMaster Universities Index of Osteoarthritis (WOMAC). The ICF Comprehensive Core Set for OA was filled by health professionals. The internal construct validities of "Body Functions-Body structures" (BF-BS), "Activity" (A), "Participation" (P) and "Environmental Factors" (EF) domains were tested by Rasch analysis and reliability by internal consistency and person separation index (PSI). External construct validity was evaluated by correlating the Rasch transformed scores with SF-36 and WOMAC.

RESULTS

In each scale, some items showing disordered thresholds were rescored, testlets were created to overcome the problem of local dependency and items that did not fit to the Rasch model were deleted. The internal construct validity of the four scales (BF-BS 16 items, A 8 items, P 7 items, EF 13 items) were good [mean item fit (SD) 0.138 (0.921), 0.216 (1.237), 0.759 (0.986) and -0.079 (2.200); person item fit (SD) -0.147 (0.652), -0.241 (0.894), -0.310 (1.187) and -0.491 (1.173) respectively], indicating a single underlying construct for each scale. The scales were free of differential item functioning (DIF) for age, gender, years of education and duration of disease. Reliabilities of the BF-BS, A, P, and EF scales were good with Cronbach's alphas of 0.79, 0.86, 0.88, and 0.83 and PSI's of 0.76, 0.86, 0.87, and 0.71, respectively. Rasch scores of BF-BS, A, and P showed moderate correlations with SF-36 and WOMAC scores where the EF had significant but weak correlations only with SF36-Social Functioning and SF36-Mental Health.

CONCLUSION

Since the four different scales derived from BF-BS, A, P, and EF components of the ICF core set for OA were shown to be valid and reliable through a combination of Rasch analysis and classical psychometric methods, these might be used as clinical assessment tools.

Systematic literature review on ICF from 2001 to 2009: its use, implementation and operationalisation

PURPOSE

To present a systematic literature review on the state of the art of the utilisation of the International Classification of Functioning, Disability and Health (ICF) since its release in 2001.

METHOD

The search was conducted through EMBASE, MEDLINE and PsychInfo covering the period between 2001 and December 2009. Papers were included if ICF was mentioned in title or abstract. Papers focussing on the ICF-CY and clinical research on children and youth only were excluded. Papers were assigned to six different groups covering the wide scenario of ICF application.

RESULTS

A total of 672 papers, coming from 34 countries and 211 different journals, were included in the analysis. The majority of publications (30.8%) were conceptual papers or papers reporting clinical and rehabilitation studies (25.9%). One-third of the papers were published in 2008 and 2009.

CONCLUSIONS

The ICF contributed to the development of research on functioning and on disability in clinical, rehabilitation as well as in several other contexts, such as disability eligibility and employment. Diffusion of ICF research and use in a great variety of fields and scientific journals is a proof that a cultural change and a new conceptualisation of functioning and disability is happening.

Application of the brief international classification of functioning, disability, and health core set as a conceptual model in distal radius fractures

PURPOSE

In 2009, the World Health Organization published a conceptual outcome framework for evaluating upper extremity injury and disease, known as the Brief International Classification of Functioning, Disability, and Health (ICF) Core Set for Hand Conditions. The purpose of this study was to apply the ICF conceptual model to outcomes for distal radius fractures (DRFs) and determine the contribution of each ICF domain to patient satisfaction.

METHODS

Patient-rated and objective functional outcome data were collected at 6 weeks, 3 months, and 6 months after surgery. We measured satisfaction using a subsection of the Michigan Hand Outcomes Questionnaire (MHQ) satisfaction score. Measured study variables were linked to their corresponding ICF domain (personal factors, environmental factors, activity and participation, and body function). We then used hierarchical regression to assess the contribution of each ICF domain to variation in overall patient satisfaction at each time point.

RESULTS

We enrolled 53 patients with unilateral DRFs treated with the volar locking plating system. Regression analysis indicated that measured study variables explain 93% (6 weeks), 98% (3 months), and 97% (6 months) of variation in patient satisfaction. For all 3 study assessment dates, activity and participation variables (MHQ-Activities of Daily Living, MHQ-Work, and Jebsen-Taylor Score) contributed the most to variation in patient satisfaction, whereas personal and environmental factors had a considerably smaller role in predicting changes in patient satisfaction.

CONCLUSIONS

The results demonstrated that it is possible to reliably model the relative contributions of each ICF domain to patient satisfaction over time, and the findings are consistent with previous research (ie, that most outcome variation is due to physical or functional factors). These results are strong enough to support continued use and further research using the ICF model for upper extremity outcomes.

Use of the International Classification of Functioning, Disability and Health to identify preliminary comprehensive and brief core sets for Guillain Barre syndrome

PURPOSE

To identify the preliminary comprehensive and brief core sets for Guillain Barre syndrome (GBS), in a Delphi process using the International Classification of Functioning, Disability and Health (ICF).

METHOD

Focus groups and a consensus process were used to identify ICF core sets for GBS. This included: preliminary ICF studies; empirical patient data collection for 77 GBS participants; review of the evidence base and treatment in GBS literature followed by a Delphi exercise with 23 physicians and allied health professionals in Melbourne, Australia.

RESULTS

The expert consensus selected 99 second level ICF categories (in three rounds) which identify health domains relevant to GBS for multidisciplinary assessment. These domains were consistent with current practice and existing GBS literature. The comprehensive core set includes: 27 (23%) categories from the component 'body function', 7 (12%) categories from 'body structures', 43 (36%) from 'activities and participation' and 22 (29%) from the component 'environmental' factors. The brief set comprised 20 categories, 20% of categories in the comprehensive core set.

CONCLUSION

The core set categories for GBS-related health need to be addressed in multidisciplinary care programs. Future clinical 'rating' of this set may facilitate scale development using the ICF in GBS. Further research is needed to confirm the generalisability of this set in clinical settings.

Applying the impairment, activity limitation, and participation restriction constructs of the ICF model to osteoarthritis and low back pain trials: a reanalysis

OBJECTIVE

To test the hypothesis that interventions targeting the relief of pain and disability in musculoskeletal diseases may have differential effects on activity limitation and participation restriction as defined in the International Classification of Functioning, Disability and Health (ICF).

METHODS

Full data were obtained for 3 randomized controlled trials that used the Western Ontario and McMaster Universities Osteoarthritis Measure (WOMAC), the Medical Outcomes Study Short-form 36 (SF-36), or the Oswestry Disability Questionnaire as their primary outcome measures. The trial outcomes were reanalyzed using items previously designated as assessing pure activity limitation (A) or participation restriction (P), or a mixture of the 2 (A/P) only, and the results compared with the outcomes found using the full scales, which assess a mixture of outcome domains.

RESULTS

The results did not refute the hypothesis. An exercise-based intervention and injection therapies both appeared to have more effect on participation restriction (P) than on activity limitation (A), while a drug-based intervention had more effect on A than on P.

CONCLUSION

Different interventions used to treat musculoskeletal disorders may have differential effects on impairment, activity limitation, and restricted participation. The use of outcome measures that do not differentiate these 3 domains may obscure the true value of an intervention.

Development of ICF core sets for head and neck cancer

BACKGROUND

Based on the International Classification of Functioning (ICF)-Disability and Health, participants from different professional and cultural backgrounds were invited to achieve consensus on a first version of ICF Core Set for head and neck cancer (HNC). It was designed to set standards for the assessment of functioning in HNC.

METHODS

The ICF was adopted by the World Health Organization (WHO) in 2001 and was used as the frame of reference. Preselection of potential ICF categories was based on 4 different preparatory studies: patient interviews, health professional surveys, literature review, and multicenter study applying ICF-nomenclature. After training on the ICF, the results of preparatory studies were presented to 21 invited participants to vote in a formal consensus process on both the Brief and Comprehensive ICF Core Set for HNC. Participants came from all 6 WHO world regions, covering 12 different countries. Professional backgrounds included otorhinolaryngologists, maxillofacial surgeons, medical/radiation oncologists, psychologists, physiotherapists, nurses, and social workers.

RESULTS

The Comprehensive ICF Core Set for HNC included 112 categories (8% of entire ICF) and the Brief ICF Core Set for HNC included 19 categories (1% of ICF).

CONCLUSION

A first version of ICF Core Sets for HNC was defined. Further validation is in process.

Validation of the World Health Organization disability assessment schedule II (WHODAS-II) in patients with osteoarthritis

The objective of this study is to test the reliability and validity of WHODAS-II (Turkish version) for the assessment of disability in patients with osteoarthritis. This study is designed as follows: the internal construct validity of WHODAS-II in patients with knee osteoarthritis was assessed by Rasch analysis, and external construct validity by association with the Western Ontario and McMaster Universities Index of Osteoarthritis (WOMAC) and the Nottingham Health Profile (NHP); reliability was tested by internal consistency, intra-class correlation coefficient (ICC) and test-retest ICC. Our study presents the results of 225 outpatients assessed with mean age 58.4 years (SD 11.1) of whom 80.9% were female. Cronbach's α, ICC, and test-retest ICC values for the six subscales of WHODAS-II varied between 0.71 and 0.94, 0.71 and 0.94, and 0.87 and 0.97, respectively. Rasch analysis of WHODAS-II indicated that after adjustment for local dependency, satisfactory fit was achieved. Two separate 'activities' and 'participation' components could also be identified. External construct validity of the scale was confirmed with expected correlations with WOMAC and NHP. This study concludes that WHODAS-II provides a reliable and valid health status instrument for measuring disability and components of 'activities' and 'participation' in patients with osteoarthritis. Thus, it provides the opportunity to model the consequences of disease according to the International Classification of Functioning, Disability and Health framework.

Measuring the ICF components of impairment, activity limitation and participation restriction: an item analysis using classical test theory and item response theory

BACKGROUND

The International Classification of Functioning, Disability and Health (ICF) proposes three main health outcomes, Impairment (I), Activity Limitation (A) and Participation Restriction (P), but good measures of these constructs are needed The aim of this study was to use both Classical Test Theory (CTT) and Item Response Theory (IRT) methods to carry out an item analysis to improve measurement of these three components in patients having joint replacement surgery mainly for osteoarthritis (OA).

METHODS

A geographical cohort of patients about to undergo lower limb joint replacement was invited to participate. Five hundred and twenty four patients completed ICF items that had been previously identified as measuring only a single ICF construct in patients with osteoarthritis. There were 13 I, 26 A and 20 P items. The SF-36 was used to explore the construct validity of the resultant I, A and P measures. The CTT and IRT analyses were run separately to identify items for inclusion or exclusion in the measurement of each construct. The results from both analyses were compared and contrasted.

RESULTS

Overall, the item analysis resulted in the removal of 4 I items, 9 A items and 11 P items. CTT and IRT identified the same 14 items for removal, with CTT additionally excluding 3 items, and IRT a further 7 items. In a preliminary exploration of reliability and validity, the new measures appeared acceptable.

CONCLUSION

New measures were developed that reflect the ICF components of Impairment, Activity Limitation and Participation Restriction for patients with advanced arthritis. The resulting Aberdeen IAP measures (Ab-IAP) comprising I (Ab-I, 9 items), A (Ab-A, 17 items), and P (Ab-P, 9 items) met the criteria of conventional psychometric (CTT) analyses and the additional criteria (information and discrimination) of IRT. The use of both methods was more informative than the use of only one of these methods. Thus combining CTT and IRT appears to be a valuable tool in the development of measures.