2.5 Meta Analysis
Statistical analysis was performed using RevMan software (Review Manager
version 5.3, Nordic Cochrane Centre, Copenhagen, Denmark). A p-value of
<0.05 was considered significant. Mean difference with a 95%
confidence interval was utilized to describe continuous outcomes, and
odds ratio with a 95% confidence interval was used to describe
dichotomous outcomes. A random effects model was used in case of
significant heterogeneity, and a fixed effect model was applied when
heterogeneity was low. Heterogeneity was assessed using the Cochrane Q
square test (P < 0.05 was considered an indicator of
significant heterogeneity) and the I2 estimates (
< 50% low heterogeneity, > 50% high
heterogeneity).