Credibility of a newly designed placebo needle for clinical trials in acupuncture research

Objective: To test the credibility of a newly designed placebo needle for acupuncture research. Design: Analysis of data on credibility of true and placebo interventions of a randomised, placebo-controlled, patient- and evaluator-blind clinical trial. Patients and Setting: The study was carried out at a university department for physical medicine and rehabilitation. 68 patients (age 48.1 +/- 14.1 years, mean +/- SD) fulfilling the criteria of the International Headache Society for tension-type headache were enrolled into the study. Interventions: Group 1 (treatment) was assigned to traditional needle placement and manipulation, whereas in group 2 (control) a new placebo device was used. Outcome Parameters: After the first treatment with real or placebo acupuncture, patients were asked to fill in a questionnaire on credibility. In addition, after 3 or 4 treatments, patients were asked for the feeling of needle insertion and deqi. Results: No difference between real and placebo acupuncture was detected with respect to the credibility of the treatment (p > 0.05). Needle insertion was recognised in all patients in the real acupuncture group and in all but 4 patients of the placebo group (p < 0.05). deqi was reported by 84% of patients in the real acupuncture group and by 34% of patients in the placebo group (p < 0.001). Conclusion: Acupuncture with the placebo needle device described here is of high credibility, and does not differ from that of real acupuncture treatment. However, to achieve comparable prick sensations in both treatment conditions, careful training with the placebo needle is needed. Furthermore, from these results arise new questions with respect to the placebo response of placebo needles. Further investigations are warranted to test if placebo needles are active controls.