The data extracted was consistently collected across all eligible studies, pooled together, and tabulated in a common format in Microsoft Excel. Statistical analyses were performed on the RevMan software (Review Manager Version 5.3) and the STATA software (StataMP Version 14). As our meta-analysis included the continuity variables, i.e., the BBPS score and the dichotomous variables, i.e., willingness to repeat rate, they were separately calculated and displayed using the forest plots with fixed or random effects model. For dichotomous events, the relative risk (RR) along with 95% confidence intervals (CI) was calculated. As the outcomes included were continuous variables, the pooled estimates were calculated as mean differences (MD) as well as 95% CI. Statistical heterogeneity among the trials was assessed by I2 measure of inconsistency and a P value, which was significant if I2 was >50% or P < 0.10. If statistically significant, then study elimination analysis was conducted when possible sources of clinical heterogeneity of a certain study were observed, and a random-effects model was applied. In addition, subgroup analysis was performed when necessary.