RT Journal Article SR Electronic T1 Towards a definition of "difference" in osteoarthritis. JF The Journal of Rheumatology JO J Rheumatol FD The Journal of Rheumatology SP 427 OP 430 VO 28 IS 2 A1 N Bellamy A1 A Carr A1 M Dougados A1 B Shea A1 G Wells YR 2001 UL http://www.jrheum.org/content/28/2/427.abstract AB To assess existing information regarding detectable differences in osteoarthritis (OA), a systematic literature search was conducted up to December 1999. Thirty-three articles were considered methodologically relevant to the definition and categorization of detectable differences in OA. It was determined that the musculoskeletal literature contains a wealth of information that relates to observed changes, much of which is derived from the clinical trials literature, but there have been relatively few methodological studies that have systematically evaluated the nature, categorization, and relevance of the change. Furthermore, most of those that have been published take the perspective of an individual or groups of experts other than that of the patient. This summary of the current literature reveals that the diverse sources of information go part way towards developing an understanding of detectable differences and their importance in the area of OA research and clinical practice. Stakeholders' interests as well as factors that modulate perceptions of importance need to be taken under consideration. In particular, the patient's perspective of the importance of change at an individual level requires further evaluation. This area of clinical research is relatively underdeveloped, but there is considerable opportunity for progress.