Personal, non-commercial use only. The Journal of Rheumatology. Copyright © 2004. All rights reserved. Gilworth, et al: Quality of life and BD 931 From the Academic Unit of Musculoskeletal and Rehabilitation Medicine, University of Leeds, Leeds; Hammersmith Hospital, London; and the Arthritis and Rheumatism Council Epidemiology Research Unit, Manchester Medical School, Manchester, United Kingdom. Supported by the UK Arthritis Research Campaign (ARC). G. Gilworth, MPhil, Senior Research Fellow; M.A. Chamberlain, FRCP, Charterhouse Professor in Rehabilitation Medicine; B. Bhakta, FRCP, Senior Lecturer in Rehabilitation Medicine; A. Tennant, PhD, Professor of Rehabilitation Studies, Academic Unit of Musculoskeletal and Rehabilitation Medicine, University of Leeds; D.O. Haskard, DM, Sir John McMichael Professor of Cardiovascular Medicine and Honorary Consultant Rheumatologist, Hammersmith Hospital; A. Silman, FRCP, Professor of Rheumatic Disease Epidemiology, Arthritis and Rheumatism Council Epidemiology Research Unit, Manchester Medical School. Address reprint requests to Mrs. G. Gilworth, Academic Unit of Musculoskeletal and Rehabilitation Medicine, University of Leeds, 36 Clarendon Road, Leeds LS2 9NZ, UK. E-mail: gilworths@aol.com Submitted January 23, 2003; revision accepted October 21, 2003. Behçet’s disease (BD) is a chronic multisystem disorder characterized by vasculitis affecting small to medium size blood vessels. Although the commonest symptoms of BD relate to mucosal ulceration it can affect virtually every organ system, causing a variety of clinical problems such as arthritis, neurological impairments, pulmonary artery aneurysm, and gastrointestinal symptoms. The commonest severe manifestation is uveitis, which occurs in as many as 70% of patients. There is no uniformly accepted laboratory test for diagnosis, and therefore classifying people as having BD depends on the presence of internationally agreed criteria 1 based on clinical features. The complex pattern of signs and symptoms in BD can lead to a variety of activity limitations (disability) and restriction in participation in many areas of life (handicap). A dilemma thus exists of the choice of outcome measure(s) most likely to identify change as a consequence of clinical intervention. To date the measurement of outcome in BD has mainly focused on impairments. The absence of labora- tory markers that correlated well with impairment led to the development of a standardized proforma (the BD Current Activity Form) to assess disease activity that is based on history of specific clinical features 2 . This is an impairment- based outcome measure useful in monitoring therapy. However, it takes no account of the wider impact of the condition on the individual’s lifestyle. Generic outcome measures of health status such as the Nottingham Health Profile (NHP) 3 and the Medical Outcomes Study Short-Form 36 (SF-36) 4 can appear attrac- tive as tools for measuring the influence of disease because they often measure several domains and allow for compar- isons between different conditions. However, condition- specific measures have been shown to be more sensitive to change 5 . Health utility measures, such as the EUROQoL, tend to be even more restricted, as they include only a few items concerning impairments and activity limitation and Development of the BD-QoL: A Quality of Life Measure Specific to Behçet’s Disease GILL GILWORTH, M. ANNE CHAMBERLAIN, BIPIN BHAKTA, DORIAN HASKARD, ALAN SILMAN, and ALAN TENNANT ABSTRACT. Objective. Current outcome measures for patients with Behçet’s disease (BD) are impairment- focused and do not necessarily take account of the wider impact of the condition on the individual’s lifestyle. Our aim was to develop a disease-specific measure of quality of life (QoL) for BD. Methods. The content of the BD-QoL was derived from qualitative interviews with patients using a “needs-based” approach to identify items. A postal survey was used to test the scaling properties, reliability, internal consistency, and validity of the new questionnaire using Rasch analysis. A second postal survey was used to assess test-retest reliability and internal consistency and to provide further evidence of the validity of the questionnaire. Results. Main themes emerging from the qualitative interviews included relationships, emotions, limitations in day to day activities, and self-image. From these themes 71 statements were chosen as potential items for the BD-QoL. After analysis, 30 items of the BD-QoL emerged free of item bias for age and sex. Fit to the Rasch model was excellent. In the second postal survey test-retest relia- bility of the 30 item BD-QoL was 0.84. Conclusion. The BD-QoL provides the clinician with a simple, reliable, and valid tool for assessing the influence of interventions for BD and for evaluating models of service delivery. It is well accepted by patients, and has excellent scaling and psychometric properties. The BD-QoL comple- ments information obtained through BD-specific disease activity scales. (J Rheumatol 2004;31:931–7) Key Indexing Terms: BEHÇET’S DISEASE OUTCOME QUALITY OF LIFE QUESTIONNAIRE Personal, non-commercial use only. The Journal of Rheumatology Copyright © 2004. All rights reserved. www.jrheum.org Downloaded on April 26, 2022 from