Table 2.

Raw data and methodological quality of included trials

Studies	Region	Sequence generation	Allocation concealment	Blind	Outcome data	Selective outcome reporting	Other sources of bias	ITT	Risk of bias
Yuquan L 2005 [25]	Single center	–	Insufficient	Unclear	Yes	No	Unclear	Yes	Unclear risk of bias
Do W 2005 [20]	Single center	Random number table (SPSS)	Insufficient	Unclear	Yes	No	Unclear	Yes	Unclear risk of bias
Yanhao W 2006 [13]	Single center	Random number table (SPSS)	Insufficient	Unclear	Yes	No	Unclear	Yes	Unclear risk of bias
Zhijun W [26]	Single center	–	Insufficient	Unclear	Yes	No	Unclear	Yes	Unclear risk of bias
Shimeng F 2010 [22]	Single center	Random number table (SPSS)	Insufficient	Unclear	Yes	No	Unclear	Yes	Unclear risk of bias
Hua Z 2010 [9]	Single center	Random number table (SPSS)	Insufficient	Unclear	Yes	No	Unclear	Yes	Unclear risk of bias
Xiqiang W 2010 [24]	Single center	–	Insufficient	Unclear	Yes	No	Unclear	Yes	Unclear risk of bias
Haiyan C 2015 [10]	Single center	Random number table (SAS)	Insufficient	Unclear	Yes	No	Unclear	Yes	Unclear risk of bias
Jin L 2015 [12]	Single center	–	Insufficient	Unclear	Yes	No	Unclear	Yes	Unclear risk of bias
Tao H 2016 [23]	Single center	Random number table (SPSS)	Insufficient	Clear	Yes	No	Unclear	Yes	Low risk of bias
Chun W 2016 [19]	Single center	Random number table (SPSS)	Insufficient	Clear	Yes	No	Unclear	Yes	Low risk of bias
Hua Z 2017 [21]	Single center	Random number table (SPSS)	Insufficient	Unclear	Yes	No	Unclear	Yes	Unclear risk of bias

ITT intention-to-treat