Fig. 3

A An Egger’s asymmetry plot of all data points included in the meta-analysis (n = 20) [2, 5, 14, 16, 20, 23, 26, 27, 33, 34, 59, 60, 62, 64]; 14 original studies but used and counted multiple times due to reporting on multiple radiological markers indicating presence and degree of publication bias is shown. The x-axis represents the inverse of standard error, and the y-axis the standardized treatment effect (as z-score). Furthermore, at the top of the graph different parameters of heterogeneity, including I², are shown. p-value < 0.05 is deemed to be significant and implicates publication bias. Egger’s asymmetry test yielded p = 0, calculated running an Egger’s regression (see Egger’s regression line) on the collated DOR and standard errors of all data used in the meta-analysis (n = 20). B A funnel plot is shown, which plots every study included in the meta-analysis (n = 20). 13 original studies but used and counted multiple times due to some studies reporting on multiple radiological markers) [], particularly their observed effect sizes (diagnostic odds ratio) on the x-axis against a measure of their standard error on the y-axis. Visually an n asymmetry is detected, with three outliers lying right and completely outside of the funnel (the right interrupted diagonal line), and two outliers lying right of the mean (vertical interrupted line) but inside the funnel plot