This 9-month pragmatic study compared 2 therapeutic regimens in the management of osteoarthritis of the hip and knee. Patients received either diacerein 100 mg/day plus standard osteoarthritic therapy for 6 months, followed by a 3-month monitoring period without diacerein, or standard therapy alone for the entire 9-month period. A total of 207 patients with osteoarthritis of the knee and hip were enrolled. Improvements in Lequense's functional index and quality-of-life scores (revised Arthritis Impact Measurement Scales Health Status Questionnaire and Nottingham Health Profile), and decreases in nonsteroidal anti-inflammatory drug and analgesic consumption were significantly greater with diacerein plus standard therapy than with standard therapy alone. The overall assessment of therapy by patients was good or excellent for 60% of those who received diacerein plus standard therapy, compared with 26% who received standard therapy alone. Medical and paramedical procedures carried out in addition to those stipulated in the protocol (medical consultations, physiotherapy, nursing, etc.), osteoarthritis-related, were fewer and less costly in the diacerein plus standard therapy group than in the standard therapy group. The average outpatient cost (in 1995 French francs) of osteoarthritis treatment in the standard therapy group was FF2272 compared with FF2360 in the diacerein plus standard therapy group. The cost-effectiveness ratios per point scored on Lequesne's index were FF1893 for the standard therapy group and FF1072 for the diacerein plus standard therapy group, leading to a saving of 43% with diacerein plus standard therapy. The marginal cost (additional cost corresponding to the clinical benefit obtained by adding diacerein to standard treatment) was FF88 per point scored on Lequesne's index.