Design of clinical trials in knee osteoarthritis: practical issues for debate

Abstract

A number of guidelines on the conduct of clinical trials in osteoarthritis (OA) have been published in recent years [1–3]. Such guidelines are useful in suggesting, amongst others: appropriate case definitions, inclusion and exclusion criteria and outcome measures. These guidelines can be used in trials of drugs that may modify symptoms and/or structural change. Such consensus statements should encourage more thoughtful, more consistent and hopefully better study designs. Greater homogeneity also permits wider inclusion of study data within systematic reviews and meta-analyses. A number of practical and theoretical issues still need to be addressed, and subjected to wider discussion. Particularly important we feel are those which may adversely affect patient recruitment, drop-out rate, and generalizability of study findings. We believe that the following aspects of knee OA drug clinical trials, in particular, require further debate.