[Discussion of optimization of sham acupuncture setting based on a clinical trial about acupuncture treatment of migraine published in British Medical Journal].

In the randomized controlled clinical trials of acupuncture, the setting of the control group (sham acupuncture) directly affected the interpretations about their outcomes (beyond placebo), and has been being the hot spot and difficult problem. In the present paper, we discussed various types of sham acupuncture (invade and non-invade needling) commonly used nowadays and made an in-depth analysis on the factors contributing to the successful blinding to patients with episodic migraine without aura in a clinical study published in British Medical Journal (2020, 368:m697). Moreover, we put forward some thoughts on how to optimize the setting of sham acupuncture in the treatment of pain diseases. These thoughts are 1) setting different placebo control group for different types of pain, 2) selecting conventional acupoints not associated with the disease, 3) selecting the most sui-table type of placebo acupuncture through pre-tests, 4) choosing the distal non-meridian and non-acupoint not in the same neuronal segment with the pain locus when using non-invade consolation needling, 5) trying best to reduce the patients' doubts about placebo acupuncture operation, 6) selecting subjects with little or without acupuncture experience for multicenter studies, and 7) trying best to select objective indicators and to avoid the subjects' report bias when evaluating the effects of acupuncture and consolation acupuncture.