3.4.1. Method of Intervention
111 studies [7, 10, 12–14, 16–26, 28, 29, 31–34, 36, 39, 42, 43, 46–59, 61, 63, 64, 66–68, 75, 78, 82, 83, 85–88, 90, 91, 93–95, 97–100, 102–106, 108–114, 125–129, 132, 135–139, 142, 144, 145, 148, 149, 151, 153, 154, 156, 157, 163–165, 167, 172, 174–176] chose manual acupuncture as intervention method. 32 studies [27, 37, 38, 44, 60, 62, 65, 69, 70, 72, 76, 77, 80, 84, 89, 96, 101, 107, 115–117, 124, 140, 146, 152, 159, 162, 166, 169–171, 173] chose electroacupuncture as intervention method. Besides, the transcutaneous electric acupoint stimulation was performed in 6 studies [45, 73, 74, 81, 141, 143], the laser acupuncture in 6 studies [40, 79, 92, 150, 160, 168], heat stimulation on acupoints in 2 studies [147, 155], and the magnetic stimulation on acupoints in 1 study [30]. There were 10 studies [11, 15, 35, 41, 71, 131, 133, 134, 158, 161] using at least two types of acupuncture methods (Figure 3).