Statistical Analysis
We used R version 4.3.0 for performing the statistical analysis.
I2 and χ2 statistics were applied
for assessing the heterogeneity of the studies and the significance
level for heterogeneity between the studies was considered
I2 > 50% and P value <0.1. We
used a random effect model so as to compute Pooled Hazard Ratio with
95% confidence interval and the Inverse Variance method was applied to
weight the studies. The researchers also used funnel plot and Eggers’
test to check the publication bias in the studies and the asymmetric
funnel plot was considered as a possible publication bias. Sensitivity
analysis was utilized to examine the heterogeneity source between the
records. The significance level in this study was considered <
0.05.
Figure 1. PRISMA flow diagram illustrating the process of
selection studies in the meta-analysis