Background: A problem acupuncture research has to face is the concept of a control group. If, in control groups, non-acupoint needling is done, physiological acupuncture effects are implied. Therefore the effects shown in this group are often close to those shown in the acupuncture group. In other trials, control groups have received obviously different treatments, such as transcutaneous electrical nervous stimulation or TENS-laser treatment; it is not clear if the effects of acupuncture are due only to the psychological effects of the treatment.
Methods: We developed a placebo acupuncture needle, with which it should be possible to simulate an acupuncture procedure without penetrating the skin. In a cross-over experiment with 60 volunteers we tested whether needling with the placebo needle feels any different from real acupuncture.
Findings: Of 60 volunteers, 54 felt a penetration with acupuncture (mean visual analogue scale [VAS] 13.4; SD 10.58) and 47 felt it with placebo (VAS 8.86; SD 10.55), 34 felt a dull pain sensation (DEQI) with acupuncture and 13 with placebo. None of the volunteers suspected that the needle may not have penetrated the skin.
Interpretation: The placebo needle is sufficiently credible to be used in investigations of the effects of acupuncture.