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Developing and validating a sham acupuncture needle
  1. Jongbae J Park
  1. Correspondence to Dr Jongbae J Park, University of North Carolina at Chapel Hill, 101 Manning Drive, Campus Box 7200, N1181 Memorial Hospital, Chapel Hill 27519-7200, NC, USA; Jongbae_park{at}

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The development of adequate controls has been an ongoing challenge in the effort to scientifically evaluate the safety and efficacy of acupuncture. Despite several sham acupuncture control devices previously reported, the development of a new sham acupuncture device that can be used as a control for different style of acupuncture may still be needed. A sham device for acupuncture interventions in which the needle is briefly manipulated up and down, rather than left in situ, would be an important contribution to evaluate the effectiveness of such an experimental intervention. Tough and colleagues report on their efforts to develop this type of device (see page 118).

Building on evidence that suggests that the least active and most credible control for true acupuncture is a non-penetrating needle, the authors designed a blunt non-penetrating needle that could be manipulated in a manner identical to a true acupuncture needle. To evaluate the usefulness of the device as a sham control for true acupuncture, the authors conducted a pilot study in which patients with whiplash injury were randomised to either the sham device or true acupuncture. Patients were blinded with respect to the treatment.

The results of the validation seem promising. A large majority of patients in both treatment groups concluded they had been treated with true acupuncture, rather than the sham acupuncture, and patients in the two treatment groups reported similarly high confidence in the effectiveness of their treatment. The lack of statistically significant differences between the two groups is encouraging, but inconclusive given the relatively small sample size. The authors provide some useful suggestions on the design and implementation of a more definitive acupuncture study using this sham device as a control. Given the detail of the suggestions and the study itself, it is hoped that such a study can be undertaken in the near future.

A particular strength of the pilot study was the consideration given to the potential for non-specific treatment effects. It has been widely observed that true acupuncture does not significantly outperform sham acupuncture, while both have been shown to perform significantly better than no treatment. This seeming paradox may reflect non-specific effects associated with acupuncture treatment due to treatment components such as device-related rituals and the patient’s confidence in and expectations of the treatment. The authors should be commended on the great care that was taken in designing the pilot study to ensure that the treatment experience with the sham device was indistinguishable from that of true acupuncture, providing greater confidence that the only difference between the two groups was in the two devices.

Looking forward, the challenge remains to identify those non-specific components of acupuncture treatment that have active physiological effects so that these components can be purposely excluded from sham procedures. This will allow a more efficient design of sham protocols and hopefully shed some light on the question of why such a small effect size has been observed between true acupuncture and sham controls.

Last but not least, as a researcher who developed one of the non-penetrating sham acupuncture devices and has been focusing on how to interpret the findings of trials using such a sham control, I would like to voice a concern. That is the fact that efforts to establish the credibility of the sham control against the experimental intervention may result in compromising the intensity of the experimental intervention in the study setting while strengthening that of the control, in which case the external validity of the study is jeopardised. This plausible hypothesis would require evidence to confirm.

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  • Competing interests None.

  • Provenance and peer review Commissioned; not externally peer reviewed

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