Researchers studying the effects of acupuncture for chronic prostatitis/chronic pelvic pain syndrome, randomised 89 patients into two groups, receiving either true or sham acupuncture, twice-weekly over ten weeks. (The sham group acted as a control and were lead to believe they were experiencing real acupuncture.) In the true acupuncture group, 73% of patients responded, compared to only 47% in the sham group. At follow-up 24 weeks later, this level of response was maintained by 32% of the acupuncture group and only 13% of the sham control group. Patients receiving true acupuncture were thus 2.4 times more likely to experience long-term benefit.
(Acupuncture versus Sham Acupuncture for Chronic Prostatitis/ Chronic Pelvic Pain. American Journal of Medicine, January 2008.)