Validating a New Sham (Placebo) Acupuncture Device: Two Randomized Controlled Trials

Abstract

Background For clinical trials of acupuncture, it would be desirable to have a sham procedure that is indistinguishable from the real treatment, yet inactive. A sham needle has been designed which telescopes instead of penetrating the skin. The Park Sham Device involves an improved method of supporting the sham needle and requires validation. Objective To test whether the sham procedure using the new device is: 1. Indistinguishable from real needles, and 2. Inactive. Design Two subject and assessor-blind, randomized controlled trials. Study samples: Study 1: 58 patients included in a clinical trial of acupuncture for acute stroke. Study 2: 63 healthy, acupuncture naïve, adult volunteers. Intervention: Real or sham acupuncture using the Park Sham Device. Settings: 1. District general hospital, 2. University laboratory. Measurements: 1. The form of treatment that patients believed they had received 2. Experience of de-qi, as judged by three acupuncture experts. Results Study 1: No patient in either group believed s/he had been treated with the sham needle. Study 2: In 40 volunteers for whom experts achieved consensus, the relative risk of experiencing de-qi with real acupuncture to that with sham acupuncture was 15.38 (95% CI 2.26 to 104.86). The inter-rater reliability of all 13 experts, calculated from their judgements on 10 subjects selected by randomisation, was 0.52 (95% CI 0.19 to 0.61). Conclusions Results suggest that the procedure using the new Park Sham Device is both indistinguishable from real acupuncture and inactive. It is therefore a valid control for acupuncture trials. The findings also lend support to the existence of de-qi, a major concept underlying traditional Chinese acupuncture.