Objective: To compare the Osteoarthritis Research Society International (OARSI) response criteria for clinical trials with patient's global assessment in patients with osteoarthritis (OA) of the hip receiving a non-pharmacological intervention, i.e., manual therapy or exercise therapy.
Methods: Data of a randomized clinical trial on manual therapy and exercise therapy in patients with OA of the hip (n = 109) were used. Change scores of measures of hip function, range of joint motion and pain were compared between patients who were differently classified by the OARSI response criteria and the patient's global assessment (using a t test, 95% CI). Furthermore, risk ratios (with 95% CI) were calculated for the contrast between treatment outcome, using the OARSI criteria or patient's global assessment.
Results: Few patients were classified as improved (i.e., responders) with the OARSI response criteria as compared to patient's global assessment. Significantly worse outcome for hip function and pain was observed in patients who were classified as non-responders (OARSI criteria), but who considered themselves as improved (patient's global assessment). Risk ratios for the contrast between the two treatment programs (manual therapy vs exercise therapy) were similar, when using the OARSI criteria or patient's global assessment.
Conclusion: The validity of the OARSI response criteria has been previously demonstrated in OA patients treated with pharmacological interventions. The present study demonstrates the validity of the OARSI response criteria in OA patients treated with a non-pharmacological intervention, i.e., manual therapy and exercise therapy.