Meta-Analysis
Copyright ©The Author(s) 2015.
World J Gastroenterol. Aug 14, 2015; 21(30): 9209-9216
Published online Aug 14, 2015. doi: 10.3748/wjg.v21.i30.9209
Figure 2
Figure 2 Risk of bias summary in included studies. The symbol of (-) red indicates that there is a high risk of bias, of (+) green indicates a low risk of bias and of (?) yellow indicates uncertainty.