Table 1.

Characteristics of eligible studies.

References	Country	Gender		Age		No.		NOS
		Experimental	Control	Experimental	Control	Experimental	Control
Zhang and Li (2016) [23]	China	M: 17 F: 62	M: 34 F: 66	53.9 ± 9.4	51.7 ± 10.20	79	100	7
Chen and Wang (2014) [19]	China	M: 11 F: 57	M: 4 F: 16	54.41 ± 14.09	53.5 ± 10.55	68	20	7
Song et al. (2018) [16]	China	M: 7 F: 52	M: 17 F: 29	50.4 ± 14.7	44.7 ± 13.70	59	46	7
Yang et al. (2015) [18]	China	M: 83 F: 69	M: 60 F: 40	52.3 ± 15.6	52 ± 14.10	152	100	7
Wu et al. (2019) [21]	China	M: 13 F: 12	NA	48.4 ± 10.16	47.2 ± 9.98	25	25	6
Wan et al. (2016) [20]	China	M: 10 F: 35	M: 6 F: 15	41.3 ± 2.1	41.2 ± 2.30	45	21	6
Xu et al. (2017) [22]	China	M: 12 F: 47	NA	59.86 ± 11.50	NA	59	30	6
Xia et al. (2015) [17]	China	M: 22 F: 128	M: 6 F: 44	51.3 ± 18.6	45.2 ± 20.40	150	50	7
Ragab et al. (2019) [15]	Africa	M: 8 F: 40	M: 7 F: 35	48.67 ± 20.74	44.7 ± 13.70	48	42	6
Akram et al. (2018) [24]	Pakistan	M: 19 F: 27	M: 11 F: 9	54.33 ± 34.07	44.0 ± 12.59	46	20	6

M: male; F: female; No: number; NOS: Newcastle-Ottawa Scale; NA: not available.