Randomised controlled trials (RCTs) of the effects of needle or electroacupuncture on symptoms of osteoarthritis of the knee were eligible for inclusion. Studies of bee venom acupuncture were excluded. Pain was the main outcome measure and was reported using a variety of scales and measures in the included studies. Some studies also reported other outcomes, such as physical function and patient global assessment. All participants had been diagnosed through radiographic evidence and/or according to American College of Rheumatology criteria. Needle acupuncture was the commonest intervention used; four studies supplemented needle acupuncture with electroacupuncture and three studies used only electroacupuncture. Comparator treatments included sham acupuncture (delivered using varying methods), diclofenac, wait-list control, transcutaneous electrical nerve stimulation (TENS), education, placebo, ice massage and standard care (individually or in combination). The number of sessions ranged from six to 23. Treatment periods ranged from less than four weeks to 26 weeks.
The authors stated neither how studies were selected for the review nor how many reviewers performed the selection.