Table 2.

Methodological quality assessment.

Year	First author	Randomization	Blinding	Allocation concealment	Withdrawals and dropouts	Reason of dropouts and withdrawals	Jadad score
2000	Fang [34]	Yes	Yes	NMT	NMT	No	3
2002	Lan [35]	Yes	No	NMT	NMT	No	2
2002	Fan [36]	Yes	No	NMT	NMT	No	2
2007	Wu [37]	Yes	No	NMT	NMT	No	2
2008	Si [38]	Yes	No	NMT	NMT	No	2
2009	Xiaochao [39]	Yes	No	NMT	NMT	No	2
2010	Jin [40]	Yes	No	NMT	NMT	No	2
2010	Xiaozhou [41]	Yes	Yes	NMT	MT	Yes	4
2011	Hui [42]	Yes	No	NMT	NMT	No	2
2011	Fang [43]	Yes	Yes	NMT	NMT	No	3
2011	Xiu [44]	Yes	Yes	MT	NMT	No	4
2012	Xianyu [45]	Yes	No	NMT	NMT	No	2
2012	Sheng [46]	Yes	No	NMT	NMT	No	2
2012	Guiying [47]	Yes	Yes	NMT	MT	Yes	4
2012	Gengliang [48]	Yes	Yes	NMT	MT	Yes	4
2012	Baowen [49]	Yes	Yes	MT	MT	Yes	5
2013	Enli [50]	Yes	No	NMT	NMT	No	2
2013	Xiaomin [51]	Yes	No	NMT	NMT	No	2
2013	Jing [52]	Yes	No	NMT	NMT	No	2
2013	Jie [53]	Yes	No	NMT	NMT	No	2
2013	Xiao [54]	Yes	No	NMT	NMT	No	2
2013	Shijing [55]	Yes	No	NMT	NMT	No	2
2013	Wu [56]	Yes	No	NMT	NMT	No	2
2013	Wu [57]	Yes	No	NMT	NMT	No	2
2014	Liucun [58]	Yes	No	NMT	NMT	No	2
2015	Maoqing [59]	Yes	No	NMT	NMT	No	2

MT: mentioned; NMT: not mentioned.