Figure 3: Funnel plot of all included studies did not show asymmetry.

Statistical analysis suggested no evidence of publication bias with Begg test and Egger text (P = 0.198 and P = 0.431, respectively). RR, risk ratio; SE, standard error.
Statistical analysis suggested no evidence of publication bias with Begg test and Egger text (P = 0.198 and P = 0.431, respectively). RR, risk ratio; SE, standard error.