highly significantp < 0.001
As expected, in the overall analysis of these eight trials, the between-trial heterogeneity was highly significant (concordance = 0.687 with standard error = 0.019; likelihood ratio test = 97.96 on 2 df, p < 0.001; Wald test = 40.92 on 2 df, p < 0.001). 4.