Tapping-in Method (Skin Penetration Technique) with a Placebo Needle for Double-Blind Acupuncture Trials.

Abstract Objectives: This study investigated the effect of acupuncture needles developed for double-blind (practitioner-patient blinding) trials employing a tapping-in method that is commonly used to penetrate the skin in Japanese-style acupuncture. Design, subjects, and interventions: An acupuncturist applied a penetrating, a skin-touch placebo, and a no-touch control needle designed to blind both practitioners and patients in the forearm in 80 healthy subjects (patients) by tapping-in method. Setting: The setting was a practice room of the Japan School of Acupuncture, Moxibustion and Physiotherapy, Tokyo, Japan. Outcome measures: The outcome measures were the acupuncturist's and subjects' guesses at the type of needles and confidence of their guesses on a 100-mm visual analogue scale (VAS). The subjects were asked about pain with needle application. Results: The number of correct/incorrect guesses (the latter including unidentified) of the acupuncturist were 73/167 with a confidence of 55.2±16.9 (mean±standard deviation) on the VAS. The subjects identified 148 needles correctly and 92 needles incorrectly, the mean confidence being 71.0±28.4. There were a few penetrating and skin-touch placebo needles that the subjects guessed as "no-touch." Whereas few of the 80 no-touch control needles were guessed as "penetrating," 16% of them were guessed as "skin-touch" and 11% were reported as "unidentifiable" by the subjects. Forty percent (40%) of the penetrating needles and 50% of the skin-touch placebo needles did not elicit skin penetration pain. Conclusions: The effect of practitioner blinding employing the needles for double blinding with the tapping-in method was satisfactory. It was difficult to blind the subjects when no-touch control needles together with penetrating and skin-touch placebo needles were used.
PMID: 23098695