Using the International Classification of Function, Disability and Health (ICF) to Compare Areas of ANCA-Associated Vasculitits (AAV) Measured in Clinical Trials to those Important to Patients with AAV and Clinicians who are Involved in their Care

Abstract

Background: The International Classification of Function, Disability and Health (ICF) describes health using 1424 categories from 4 components: body functions (BF), body structures (BS), activities and participation (AP) and contextual factors (environmental (EF) and personal (PF)). In this study the ICF was used to describe and compare aspects of ANCA-Associated Vasculitis (AAV) measured in clinical trials and those important to clinicians and patients. Methods: Individual interviews and focus groups were used to capture the perspective of AAV patients. Clinicians’ perspective was obtained with an email-based questionnaire. Outcomes used in AAV randomized trials were extracted from results of a systematic review of literature. Identified concepts were mapped to the ICF according to previously published ICF linking rules, and the resulting lists of relevant AAV outcomes were compared descriptively. Results: Twelve individual interviews and 2 focus groups represented the patient perspective while responses from 27 clinicians yielded the clinicians’ perspective. Systematic literature review identified 67 clinical trials and 28 abstracts from which measured outcomes were extracted. All three perspectives demonstrated detailed coverage of ICF components BF and BS. In the component AP patients and clinicians identified similar ICF categories, a number of which were under-sampled by AAV trials. Contextual factors appear to be significantly more relevant to patients than clinicians and researchers. Conclusion: Patients and clinicians have different views of the relevance of various AAV outcomes, and these views differ from what is measured in clinical trials of AAV. This highlights the need for a broad and standardized approach to developing and selecting outcomes for complex medical conditions such as AAV.