Degenerative joint disease.

We have focused on several features somewhat unique to OA which require special attention relative to clinical trials. These include disease classification, for which the schema in Table 1 was developed, patient selection and admission criteria, and the choice of appropriate clinical outcome parameters. We suggest the following: That future trials be limited to patients with idiopathic OA with specified joint groups involved. That pain, assessed with a visual analogue scale, and both the patient's and investigator's global assessment be the primary clinical outcome variables to be analysed. That concomitant analgesic agents not be used during anti-inflammatory drug trials to prevent confounding pain relief as an outcome variable. That future, long-term studies use validated health status measures to assess functional outcomes.