Wang JW 2005[11]
|
Multi-center
|
Random number table (SAS)
|
Insufficient
|
Clear
|
No
|
No
|
Unclear
|
Yes
|
Low risk of bias
|
Yang L 2005[12]
|
Multi-center
|
Random number table (SPSS)
|
Unclear
|
Unclear
|
Yes
|
No
|
Unclear
|
No
|
Unclear risk of bias
|
Cai L 2007[13]
|
Single center
|
Random number table (SPSS)
|
Unclear
|
Clear
|
Yes
|
No
|
Unclear
|
No
|
Low risk of bias
|
Mu HY 2009[14]
|
Single center
|
Random number table (SPSS)
|
Unclear
|
Clear
|
Yes
|
No
|
Unclear
|
No
|
Low risk of bias
|
Liao HY 2009[15]
|
Single center
|
Random number table (SPSS)
|
Unclear
|
Unclear
|
Yes
|
No
|
Unclear
|
No
|
Unclear risk of bias
|
Zhang T 2009[16]
|
Single center
|
Random number table (SPSS)
|
Unclear
|
Clear
|
Yes
|
No
|
Unclear
|
No
|
Low risk of bias
|
Liu J 2009[17]
|
Single center
|
Random number table (SPSS)
|
Unclear
|
Unclear
|
Yes
|
No
|
Unclear
|
No
|
Unclear risk of bias
|
Ma JB 2009[18]
|
Single center
|
Random number table (SPSS)
|
Unclear
|
Unclear
|
Yes
|
Yes
|
Unclear
|
No
|
Unclear risk of bias
|
Shi GY 2009[19]
|
Multi-center
|
Random number table (SAS)
|
Unclear
|
Unclear
|
Yes
|
No
|
Unclear
|
No
|
Unclear risk of bias
|
Han BH 2011[20]
|
Multi-center
|
Random number table (SPSS)
|
Insufficient
|
Clear
|
Yes
|
No
|
Unclear
|
No
|
Low risk of bias
|
Zhao X 2011[21]
|
Single center
|
Random number table (SPSS)
|
Unclear
|
Clear
|
Yes
|
No
|
Unclear
|
No
|
Low risk of bias
|
Hu HT 2011[22]
|
Single center
|
Random number table (SPSS)
|
Unclear
|
Unclear
|
Yes
|
No
|
Unclear
|
No
|
Unclear risk of bias
|
Wen F 2011[23]
|
Single center
|
Random number table (SPSS)
|
Unclear
|
Unclear
|
Yes
|
No
|
Unclear
|
No
|
Unclear risk of bias
|
Zhang H 2011[24]
|
Multi-center
|
unclear
|
Unclear
|
Unclear
|
Yes
|
No
|
Unclear
|
No
|
Unclear risk of bias
|
Chen Q 2011[25]
|
Single center
|
Random number table (SPSS)
|
Unclear
|
Unclear
|
Yes
|
No
|
Unclear
|
No
|
Unclear risk of bias
|