Nenad Kostanjsek

ICF linking rules : an update based on lessons learned

OBJECTIVE Outcome research seeks to understand the end results of health services. Researchers use a wide variety of outcome measures including technical, clinical and patient-oriented measures. The International Classification of Functioning, Disability and Health (ICF) as a common reference framework for functioning may contribute to improved outcome research. The objective of this paper is to provide an updated version of the linking rules published in 2002 and illustrate how these rules are applied to link technical and clinical measures, health-status measures and interventions to the ICF. RESULTS Three specific linking rules have been established to link health-status measures to the ICF and one specific linking rule has been created to link technical and clinical measures and interventions. A total of 8 linking rules have been established for use with all different outcome measures and with interventions. CONCLUSION The newly updated linking rules will allow researchers systematically to link and compare meaningful concepts contained in them. This should prove extremely useful in selecting the most appropriate outcome measures among a number of candidate measures for the applied interventions. Further possible applications are the operationalization of concrete ICF categories using specific measures or the creation of ICF category-based item bankings.

Development of ICF Core Sets for patients with chronic conditions

OBJECTIVE The objective of the ICF Core Sets project is the development of internationally agreed Brief ICF Core Sets and Comprehensive ICF Core Sets. METHODS The methods to develop both ICF Core Sets, the Comprehensive ICF Core Set and the Brief ICF Core Set, involved a formal decision-making and consensus process integrating evidence gathered from preliminary studies and expert opinion. RESULTS The results regarding the development of the ICF Core Sets for 12 health conditions (chronic widespread pain, low back pain, osteoarthritis, osteoporosis, rheumatoid arthritis, chronic ischemic heart disease, diabetes mellitus, obesity, obstructive pulmonary diseases, breast cancer, depression, and stroke) are presented in this supplement. CONCLUSION Both, the Brief ICF Core Sets and the Comprehensive ICF Core Sets are preliminary and need to be tested in the coming years based on a standardized protocol in close cooperation with the ICF research branch of the WHO FIC CC (DIMDI) in Munich and the CAS team at WHO. The final goals are valid and globally agreed tools to be used in clinical practice, research and health statistics.

Developing the World Health Organization Disability Assessment Schedule 2.0

OBJECTIVE To describe the development of the World Health Organization Disability Assessment Schedule 2.0 (WHODAS 2.0) for measuring functioning and disability in accordance with the International Classification of Functioning, Disability and Health. WHODAS 2.0 is a standard metric for ensuring scientific comparability across different populations. METHODS A series of studies was carried out globally. Over 65,000 respondents drawn from the general population and from specific patient populations were interviewed by trained interviewers who applied the WHODAS 2.0 (with 36 items in its full version and 12 items in a shortened version). FINDINGS The WHODAS 2.0 was found to have high internal consistency (Cronbachs alpha, α: 0.86), a stable factor structure; high test-retest reliability (intraclass correlation coefficient: 0.98); good concurrent validity in patient classification when compared with other recognized disability measurement instruments; conformity to Rasch scaling properties across populations, and good responsiveness (i.e. sensitivity to change). Effect sizes ranged from 0.44 to 1.38 for different health interventions targeting various health conditions. CONCLUSION The WHODAS 2.0 meets the need for a robust instrument that can be easily administered to measure the impact of health conditions, monitor the effectiveness of interventions and estimate the burden of both mental and physical disorders across different populations.

The International Classification of Functioning, Disability and Health: a new tool for understanding disability and health

Reliable and timely information about the health of populations is part of the World Health Organizations mandate in the development of international public health policy. To capture data concerning functioning and disability, or non-fatal health outcomes, WHO has recently published the revised International Classification of Functioning, Disability and Health (ICF). In this article, the authors briefly outline the revision process and discuss the rationale for the ICF and the needs that it serves in rehabilitation. The ICF is shown to be an essential tool for identifying and measuring efficacy and effectiveness of rehabilitation services, both through functional profiling and intervention targeting. Existing applications of the ICF in rehabilitation are then surveyed. The ICF, in short, offers an international, scientific tool for understanding human functioning and disability for clinical, research, policy development and a range of other public health uses.

Application of the International Classification of Functioning, Disability and Health (ICF) in clinical practice

(2002). Application of the International Classification of Functioning, Disability and Health (ICF) in clinical practice. Disability and Rehabilitation: Vol. 24, No. 5, pp. 281-282.

ICF Core Sets for stroke.

OBJECTIVE To report on the results of the consensus process integrating evidence from preliminary studies to develop the first version of the Comprehensive ICF Core Set and the Brief ICF Core Set for stroke. METHODS A formal decision-making and consensus process integrating evidence gathered from preliminary studies was followed. Preliminary studies included a Delphi exercise, a systematic review, and an empirical data collection. After training in the ICF and based on these preliminary studies relevant ICF categories were identified in a formal consensus process by international experts from different backgrounds. RESULTS The preliminary studies identified a set of 448 ICF categories at the second, third and fourth ICF levels with 193 categories on body functions, 26 on body structures, 165 on activities and participation, and 64 on environmental factors. Thirty-nine experts from 12 different countries attended the consensus conference on stroke. Altogether 130 second-level categories were included in the Comprehensive ICF Core Set with 41 categories from the component body functions, 5 from body structures, 51 from activities and participation, and 33 from environmental factors. The Brief ICF Core Set included a total of 18 second-level categories (6 on body functions, 2 on body structures, 7 on activities and participation, and 3 on environmental factors). CONCLUSION A formal consensus process integrating evidence and expert opinion based on the ICF framework and classification led to the definition of ICF Core Sets for stroke. Both the Comprehensive ICF Core Set and the Brief ICF Core Set were defined.

ICF CORE SETS FOR RHEUMATOID ARTHRITIS

OBJECTIVE To report on the results of the consensus process integrating evidence from preliminary studies to develop the first version of a Comprehensive ICF Core Set and a Brief ICF Core Set for rheumatoid arthritis. METHODS A formal decision-making and consensus process integrating evidence gathered from preliminary studies was followed. Preliminary studies included a Delphi exercise, a systematic review, and an empirical data collection. After training in the ICF, and based on these preliminary studies, relevant ICF categories were identified in a formal consensus process by international experts from different backgrounds. RESULTS The preliminary studies identified a set of 530 ICF categories at the second, third and fourth ICF levels with 203 categories on body functions, 76 on body structures, 188 on activities and participation, and 63 on environmental factors. Seventeen experts from 12 different countries attended the consensus conference on rheumatoid arthritis (7 physicians with at least a specialization in physical and rehabilitation medicine, 7 rheumatologists, one nurse, one occupational therapist, and one physical therapist). Altogether 96 categories (76 second-level and 20 third-, and fourth-level categories) were included in the Comprehensive ICF Core Set with 25 categories from the component body functions, 18 from body structures, 32 from activities and participation, and 21 from environmental factors. The Brief ICF Core Set included a total of 39 second-level categories, with 8 on body functions, 7 on body structures, 14 on activities and participation, and 10 on environmental factors. CONCLUSION A formal consensus process integrating evidence and expert opinion based on the ICF framework and classification led to the definition of ICF Core Sets for rheumatoid arthritis. Both the Comprehensive ICF Core Set and the Brief ICF Core Set were defined.

ICF Core Sets for low back pain

OBJECTIVE To report on the results of the consensus process integrating evidence from preliminary studies to develop the first version of a Comprehensive ICF Core Set and a Brief ICF Core Set for low back pain. METHODS A formal decision-making and consensus process integrating evidence gathered from preliminary studies was followed. Preliminary studies included a Delphi exercise, a systematic review and an empirical data collection. After training in the ICF and based on these preliminary studies, relevant ICF categories were identified in a formal consensus process by international experts from different backgrounds. RESULTS The preliminary studies identified a set of 503 ICF categories at the second, third and fourth ICF levels with 211 categories on body functions, 47 on body structures, 190 on activities and participation and 55 on environmental factors. Eighteen experts from 15 different countries attended the consensus conference on low back pain. Altogether 78 second-level categories were included in the Comprehensive ICF Core Set with 19 categories from the component body functions, 5 from body structures, 29 from activities and participation and 25 from environmental factors. The Brief ICF Core Set included a total of 35 second-level categories with 10 on body functions, 3 on body structures, 12 on activities and participation and 10 on environmental factors. CONCLUSION A formal consensus process integrating evidence and expert opinion based on the ICF framework and classification led to the definition of ICF Core Sets for low back pain. Both the Comprehensive ICF Core Set and the Brief ICF Core Set were defined.

Identification of the most common patient problems in patients with chronic conditions using the ICF checklist

OBJECTIVE To identify the most common patient problems in patients with 12 different chronic conditions using the ICF checklist. METHODS A multi-centre, cross-sectional study with convenient samples of patients who had received a clinical diagnosis of any of 12 different chronic conditions undergoing inpatient or outpatient rehabilitation. To describe the population, age, gender, and the SF-36 were recorded. Data for 917 patients from 33 rehabilitation centres were analysed. RESULTS Most of the ICF-checklist categories were common to at least 1 condition. Pain was the sole category of 125 ICF-checklist categories that was common to all chronic conditions. Patients with low back pain, rheumatoid arthritis, and diabetes mellitus did not often experience the problems listed in the ICF-checklist. CONCLUSION The main finding, that in most conditions categories from each component were common, underscores the need to address all components when assessing functioning and health in patients with chronic conditions.

Validation of the "World Health Organization Disability Assessment Schedule, WHODAS-2" in patients with chronic diseases

BackgroundThe WHODAS-2 is a disability assessment instrument based on the conceptual framework of the International Classification of Functioning, Disability, and Health (ICF). It provides a global measure of disability and 7 domain-specific scores. The aim of this study was to assess WHODAS-2 conceptual model and metric properties in a set of chronic and prevalent clinical conditions accounting for a wide scope of disability in Europe.Methods1,119 patients with one of 13 chronic conditions were recruited in 7 European centres. Participants were clinically evaluated and administered the WHODAS-2 and the SF-36 at baseline, 6 weeks and 3 months of follow-up. The latent structure was explored and confirmed by factor analysis (FA). Reliability was assessed in terms of internal consistency (Cronbachs alpha) and reproducibility (intra-class correlation coefficients, ICC). Construct validity was evaluated by correlating the WHODAS-2 and SF-36 domains, and comparing known groups based on the clinical-severity and work status. Effect size (ES) coefficient was used to assess responsiveness. To assess reproducibility and responsiveness, subsamples of stable (at 6 weeks) and improved (after 3 moths) patients were defined, respectively, according to changes in their clinical-severity.ResultsThe satisfactory FA goodness of fit indexes confirmed a second order factor structure with 7 dimensions, and a global score for the WHODAS-2. Cronbachs alpha ranged from 0.77 (self care) to 0.98 (life activities: work or school), and the ICC was lower, but achieved the recommended standard of 0.7 for four domains. Correlations between global WHODAS-2 score and the different domains of the SF-36 ranged from -0.29 to -0.65. Most of the WHODAS-2 scores showed statistically significant differences among clinical-severity groups for all pathologies, and between working patients and those not working due to ill health (p < 0.001). Among the subsample of patients who had improved, responsiveness coefficients were small to moderate (ES = 0.3-0.7), but higher than those of the SF-36.ConclusionsThe latent structure originally designed by WHODAS-2 developers has been confirmed for the first time, and it has shown good metric properties in clinic and rehabilitation samples. Therefore, considerable support is provided to the WHODAS-2 utilization as an international instrument to measure disability based on the ICF model.