highly significantp < 0.001
A random effects model using DerSimonian-Laird estimator for τ 2 was used for the pooled RR because the I 2 test of heterogeneity was highly significant ( p < 0.001) [ 22 ].
A random effects model using DerSimonian-Laird estimator for τ 2 was used for the pooled RR because the I 2 test of heterogeneity was highly significant ( p < 0.001) [ 22 ].