Setting: A hospital general internal medicine department in Texas, USA. Participants: Men and women over 49 years with knee OA according to the American College of Rheumatology criteria. Additional inclusion criteria were pain in the knee in the preceding 2 weeks, > 3/10 on a visual analogue scale, no prior treatment with acupuncture, stable treatment with nonsteroidal anti-inflammatory drugs, analgesics, or glucosamine.

Exclusion criterion was intraarticular injections in the knee in the previous 2 months. Randomisation of 560 participants allocated 238 to the high expectations group, 242 to the neutral expectations group, and 80 to the waiting list group. Interventions: : Six acupuncturists licensed in traditional Chinese medicine Baf-A1 order carried out the intervention. For the communication style intervention, providers conveyed

high expectations of improvement, GSK1120212 cell line by using positive utterances such as ‘I think this will work for you’, while neutral expectations were conveyed with uncertainty utterances such as ‘It may or may not work for you’. For the acupuncture intervention the procedure and specific points were standardised by a panel consisting of the acupuncturists in each of the 2 arms: TCA points on the basis of clinical practice, and sham points outside the relevant meridians. Outcome measures: : The primary outcomes were Joint-Specific Multidimensional Assessment of Pain (J-MAP), Cell press Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC) pain subscale, and Satisfaction with Knee Procedure (SKIP) measured at 4 weeks, 6 weeks (end of treatment), and 3 months. Results: : 527 (94%) participants completed the study. There were no significant differences between the TCA and sham groups in any of the outcome measures. Patients in the high expectations communication style group had statistically significant improvements in pain (J-MAP) and satisfaction (SKIP) compared with the neutral group. Mean differences (95% CI) at 3 months follow up were 0.4 (0.1 to 0.7) for J-MAP (1 to 7 scale), and 0.2 (0.03 to 0.3) for SKIP (1 to 5 scale). Conclusion: : In patients with knee OA, needling of meridian

points was not more effective than the use of sham points, whereas acupuncturists’ communication styles had a small but statistically significant effect on pain reduction and satisfaction. This trial raises two important research questions. First, is TCA more effective than sham acupuncture and waiting list? Second, does provider communication style have an effect on treatment response? The trial provides strong evidence that TCA is not more effective than sham acupuncture. Both interventions were more effective than waiting list though, and, given that the sham procedure was successful, the effect can be considered as a placebo effect. Further, this trial showed that communication style mattered more than the provided treatment with respect to pain perception and satisfaction.