Table 2.

Characteristics of the included reviews.

First author; year	Country	Trials (sample size)	Treatment intervention	Control intervention	Quality assessment tool	Overall conclusion
Deng [14] 2018	China	12 (933)	AT; AT + CPM; AT + MT	CPM; MT	Cochrane criteria	Acupuncture treatment of TTH has certain advantages.
Zhang et al. [15] 2018	China	10 (1071)	AT	SAT; NSAIDs	Jadad score	The acupuncture treatment is effective for TTH, and the therapeutic effect is better than NSAIDs.
Lin and Xiao [16] 2015	China	9 (598)	AT	MT	Cochrane criteria	The therapeutic effect of acupuncture on TTH has certain advantages compared with MT.
Li and Luo [17] 2005	China	13 (571)	AT	SAT; other physical therapies; MT	Jadad score	Comparing acupuncture with sham acupuncture and other treatments, current evidence cannot evaluate whether acupuncture is significantly effective for TTH.
Linde et al. [18] 2016	Germany	11 (2349)	AT	SAT; other physical therapies	Cochrane criteria	AT is effective for treating frequent episodic or chronic TTH.
Hao et al. [19] 2013	Australian	5 (838)	AT	SAT	Jadad score	AT stimulation mode, needle retention, and treatment frequency could be important factors contributing to the outcome of acupuncture for TTH.
Davis et al. [20] 2008	American	8 (896)	AT	SAT	Jadad score	The results suggest that AT compared with sham for TTH has limited efficacy for the reduction of headache frequency.
Sun and Gan [21] 2008	American	25 (3916)	AT	SAT; other physical therapies	Jadad score	AT is superior to SAT and MT in improving headache intensity, frequency, and response rate.

AT: acupuncture therapy; SAT: sham acupuncture therapy; NAT: nonacupuncture therapy; CPM : Chinese patent medicine; NSAIDs: nonsteroidal anti-inflammatory drugs; MT: medication therapy.