Table 2.

Quality evaluation of included studies

Studies	Jadad Scores	Weaknesses
Bao et al. 2005 [15]	2	NR, NF
Cao et al. 2013 [16]	2	NR, NF
Chen et al. 2013 [17]	2	NR, NF
Chen et al. 2016 [18]	2	SS, NR, NF
Duan et al. 2010 [19]	2	SS
Guo et al. 2005 [20]	2	NR, NF
Hou et al. 2018 [21]	2	NR, NF
Jiang et al. 2010 [22]	2	NR, NF
Li et al. 2006 [23]	1	NR, NF
Li et al. 2008 [24]	1	NR, NF
Li et al. 2009 [25]	2	NR, NF
Li et al. 2011 [6]	1	NR, NF
Tao et al. 2014 [26]	2	SS, NR, NF
Wang et al. 2006 [27]	3	NR
Wang et al. 2012 [28]	1	NR, NF
Wu et al. 2001 [29]	1	SS, NR, NF
Zhang Z et al. 2005 [31]	1	NR, NF
Zhang S et al. 2005 [30]	2	NR, NF
Zhang et al. 2017 [32]	2	NR, NF
Zhao et al. 2008 [34]	2	SS, NR, NF
Zhao et al. 2006 [33]	2	NR, NF
Zhou et al. 2003 [35]	1	NR, NF
Zhu et al. 2006 [36]	2	SS, NR, NF
Zou et al. 2009 [37]	1	NR, NF

SS = Small samples; NR = Adverse events unreported; NF = No follow-up