“…All but five trials [43, 44, 46, 50, 51] required the appearance of poststimulating “de-qi” sensation, a critical factor for the effectiveness of acupuncture therapy. As to control groups, sham acupuncture alone was adopted in six trials [42, 43, 45, 46, 49, 50], and nine trials [40, 41, 44, 47, 48, 51, 52, 54, 55] used medication as controls; one trial [53] applied both sham acupuncture and medication in separate control groups. As to the implementation of sham acupuncture, nonacupuncture points were used in all of the relevant trials, except one [42] that chose the sham points in different innervation area from the acupuncture group.…”