This is an area of vigorous debate, and the published literature is voluminous. Very generally, on the side for positive human clinical benefit are data from small to moderately sized clinical reports and investigations, as well as the anecdotal reports, observations and experiences of patients. On the opposite side, taken as a whole, are published data that do not support the global conclusion of clear clinical benefit for acupuncture treatment when acupuncture is evaluated using data from well-controlled and properly powered studies that constitute “gold standard evidence” in contemporary scientific medicine. There are some recent exceptions: e.g. a recently published neuroimaging study showing both an acupuncture-provoked change in brain information processing pathways linked to a measured beneficial change in patient outcome [see: Resources menu for a link to this material], but as a generalization and on the whole, the two data sources are not in agreement.
My personal approach is to acknowledge this difference, but to emphasize that, in my office-based practice, individual patient experience after a trial of acupuncture treatment, in conjunction with other recommendations for health and healing, is the most valuable measure of benefit. If my patient has a positive experience with perceived benefit, then for that individual, treatment has been helpful.