Objectives: (1) Develop a sham moxibustion device; (2) determine whether volunteer participants and practitioners can distinguish the sham procedure from real moxibustion during treatment for prevention of the common cold; and (3) assess the feasibility of conducting a larger clinical trial of the device.
Design: Double-blinded, randomized, placebo-controlled clinical trial.
Setting: A community outpatient health station in Chaoyang district, Beijing, China, from early November through late December 2003.
Methods: Sham and real moxibustion pillars were made by affixing moxa cones onto special collar bases. These pillars resemble each other in appearance, burning procedure and residue, but the base of the sham pillar isolates the moxa-produced heat and smoke and prevents them from radiating to the skin. These devices were tested in a pilot clinical trial in which patients received moxibustion at Zusanli (ST 36) for prevention of the common cold. Volunteers (n = 71) aged 55-75 years were given pre-treatment questionnaires to assess their knowledge of moxibustion and their expectations and motives for participating in the trial, randomized into treatment (n = 36) and placebo-controlled (n = 35) groups, and treated once every 2 days for 1 month. Questionnaires assessing the effectiveness of the blinding were given to the volunteers at the end of the trial and to practitioners after each treatment session.
Result: There were no significant differences between the two groups of patients in past moxibustion experience, knowledge of moxibustion, expectations and motivation. The number of volunteers in the treatment group and the placebo group who believed they received: (1) real moxibustion; (2) sham moxibustion; and (3) were uncertain as to which they received is 30, 0, 5; 29, 0, 4, respectively. The results show no significant statistical differences (P = 1.000). The number of volunteers in the treatment group and the placebo group who were believed, by the two practitioners who provided the treatments, to have received: (1) real moxibustion; (2) sham moxibustion; and (3) and an undisclosed treatment were 10, 6, 19; 9, 4, 20 and 11, 7, 17; 12, 5, 16, respectively. There were no statistically significant differences between the practitioners (P = 0.811 and 0.840).
Conclusion: The sham moxibustion device was successfully validated in the present study. The results demonstrate that these specially designed real and sham moxibustion pillars can be used together to provide an effective placebo-control in moxibustion research and can successfully fulfill the double blinding protocol in moxibustion clinical trials.