RESUMO
Differences and relations between effects of acupuncture therapy and sham acupuncture are systematically analyzed in this article through the influential factors of acupuncture effect. And it is held that sham acupuncture effect is not exactly equal to placebo effect. The effects of both acupuncture and sham acupuncture are composed by specific effects and non-specific effects, and the differences of non-specific effects between acupunc ture and sham acupuncture can be minimized furthest with blinding and randomized method. Therefore, the difference of acupuncture and sham acupuncture treatment rests with the degree of differences of the specific effects. Only when both of the specific effect of acupuncture and the effect of acupuncture are minimized, can it be applied as the ideal placebo control. Consequently when placebo acupunture are setted up, factors such as the body condition, site of stimulation and stimulation parameters which can influence the specific effect of acupuncture should be taken into consideration to produce the relatively minimum specific effect.