Table 1. Study design and quality of the included trials.

	No. of studies	No. of randomized subjects	Total Jadad score					No. of studies with Jadad score ≥3
			I	II	III	IV	V
CHM vs. placebo	2	224	0	0	0	1	1	2
CHM vs. WM	16	1225	1	9	4	0	2	6
CHM+WM vs. WM	9	819	1	7	1	0	0	1
Three- or four-arm design	4	290	1	1	1	0	1	2
Total	31	2558	3	17	6	1	4	11
%	100	100	9.7	54.8	19.4	3.2	12.9	35.5

Abbreviations: CHM, Chinese herbal medicine; WM, Western medication.