Table 1.

Details of intervention

	Intervention group	Control group
Acupoints	DU20, EX-HN3, DU24, DU26, EX-HN1, DU17, HT7, PC6, GB20, SP6	DU20, EX-HN3, DU24, DU26, EX-HN1, DU17, HT7, PC6, GB20, SP6
Depth of insertion	DU20, DU17, EX-HN3, DU24, DU26, EX-HN1, GB20, HT7; 10 mm SP6; 15 mm	No insertion
Needle type	Steel needles (Wuxi Jiajian Medical Material Co., Ltd., Wuxi, China)	Blunt-tip needle (Streitberger Placebo-needle)
Needle sensation	With de-qi sensation	Without de-qi sensation
Electric stimulation	Needles on DU20 and EX-HN3 connected to G6805-2 Multi-Purpose Health Device (Shanghai Medical Instruments High-Techno, China), with electric pulse at a frequency of 2.5 Hz and an intensity of 45 mA	Needles on DU20 and EX-HN3 connected to G6805-2 Multi-Purpose Health Device (Shanghai Medical Instruments High-Techno, China), without electric pulse
Frequency and duration	Three sessions per week for 8 weeks	Three sessions per week for 8 weeks