Acupuncture for chronic knee pain: a randomised clinical trial. Authors' reply.

Abstract

Drs White and Cummings state1 that we negatively reported findings of our ‘positive study’—namely, our trial evaluating acupuncture for chronic knee osteoarthritis (OA).2 Our study was not a ‘positive study’ as they suggest. Rather, our study showed no benefit of needle or laser acupuncture compared with sham laser acupuncture on either of our two primary outcomes (pain and function), and small clinically irrelevant benefits compared with no acupuncture for both laser and needle acupuncture. In accordance with best practice in the conduct and interpretation of clinical trials, we (1) a priori specified our primary outcome measures, including the minimum clinically important difference (MCID) on the scale of measurement for each outcome measure; (2) determined and recruited the sample size needed to show meaningful between-group differences in primary outcomes based on our chosen MCIDs and estimated SDs with adequate power; and (3) interpreted our findings based on both of these primary outcomes, their MCIDs and considering both control conditions included in our study design (ie, sham laser acupuncture and no acupuncture). Accordingly, the conclusion stating that our findings do not support acupuncture for these patients is appropriate and is the only conclusion that can (and should) be drawn from our study. We powered our study to detect the absolute MCID between groups in pain (1.8 units) and function (6 units), which have been recommended specifically for our chosen primary …