Use of a placebo control is often implemented in randomized controlled trials (RCTs) not only to evaluate the specific effect of a test intervention but also to effectively blind study participants. Unlike trials of pharmacological interventions where fabrication of placebo is relatively easy, however, inventing and/or implementing a placebo control and ensuring masking in trials assessing non-pharmacological treatments such as surgery, psychotherapy, or acupuncture, is known to be more difficult . In non-pharmacological trials, it has been challenging since detailed information on study hypothesis may compromise the success of blinding while ensuring participant’s autonomy is an essential ethical research conduct. Placebo-controlled trials of acupuncture have been in particular criticized for being stingy with placebo information disclosure to their participants [3, 4]. Such practice, i.e. partial or no information on study hypothesis and methods to the study participants, is line with one of the strategies used in studies assessing non-pharmacological treatment to achieve successful blinding .