Extended Data Fig. 8: Funnel Plots for publication bias.
Funnel plots derived from Egger’s linear regression test for publication bias. Statistical test used was two-sided. All funnel plots showed evidence of publication bias as evidenced by substantial number of points outside each funnel and points not symmetrically distributed in each funnel. However, on Egger’s test, publication bias was present in eight of the meta-analyses (b–d,f–i,j,m), with effect sizes tending to decrease as standard errors increased. Publication bias was not present in figures a and e based on the results of Egger's test.
