A Double-Blind Multicentre Comparison of Diclofenac Sodium and Naproxen in Osteoarthrosis of the Hip

Abstract

In this two-week, double-blind, between-patient trial conducted in 79 patients with osteoarthrosis of the hip, diclofenac sodium (Voltaren®) in a dosage of 50 mg b.i.d. was compared with naproxen in a dosage of 250 mg b.i.d. At the end of the trial, 81.6% of the patients treated with diclofenac sodium and 70.3 % of those treated with naproxen felt that they had experienced an improvement in the status of their arthritic condition. In this and other parameters of therapeutic efficacy a significant improvement over pre-treatment status occurred. However, no difference was detected between the two treatment groups. In this trial the four centres differed significantly with regard to characteristics of the trial population and pre-treatment severity of disease. Nevertheless, by applying the method of Mantel & Haenszel (6), it was found that there were no statistically significant differences in the. nature of the response to the two trial treatments in the various centres. Hence, the results obtained in the total trial population are considered to be valid. It is suggested that this statistical approach provides a possible means of handling clinically relevant data from a heterogeneous multicentre trial population. Unwanted effects were reported by three patients on diclofenac sodium and by two on naproxen. In one of the patients receiving naproxen, treatment had to be discontinued owing to headache, nausea, and vomiting.