There is conflicting evidence on the efficacy of Traditional Chinese Acupuncture (TCA), and the role of placebo effects elicited by acupuncturists’ behavior has not been elucidated. We conducted a 3-month randomized clinical trial in patients with knee osteoarthritis to compare the efficacy of TCA to sham acupuncture, and examine the effects of acupuncturists’ communication style.
Acupuncturists were trained to interact in one of two communication styles: ‘high’ or ‘neutral’ expectations. Patients were randomized to one of 3 groups: waiting list, ‘high’ or ‘neutral’, and nested within style, TCA or sham acupuncture over 6 weeks. Sham acupuncture was performed in non-meridian points, with shallow needles and minimal stimulation. Primary outcome measures were: Joint-specific Multidimensional Assessment of Pain (J-MAP), Western Ontario McMaster Osteoarthritis Index (WOMAC), and satisfaction.
455 patients who received treatment (TCA or sham) and 72 controls were included. No statistically significant differences were observed between TCA or sham acupuncture, but both groups had significant reductions in J-MAP and WOMAC pain compared to the waiting group (-1.1, -1.0, and -0.1, p<0.001; -13.7, -14, -1.7, p<0.001). Statistically significant differences were observed in J-MAP pain reduction and satisfaction, favoring the ‘high’ expectations group. Fifty-two percent and 43% in the TCA and sham groups thought they had received TCA (kappa=0.05), suggesting successful blinding.
TCA was not superior to sham acupuncture. However, acupuncturists’ style had significant effects on pain reduction and satisfaction, suggesting that the analgesic benefits of acupuncture can be partially mediated through placebo effects related to the acupuncturist's behavior.