Fig. 2: Bubble plot of meta-regression and influence plot of sensitivity analysis.

a Bubble plot with fitted meta-regression line. Trial-level association between the hazard ratio for disease-free survival and shortened trastuzumab treatment time. The size of the circles in the plot is inversely proportional to the variance of the log odds ratio, so larger circles correspond to larger studies. b Sensitivity analysis. Influence of individual studies on the summary effect. The vertical axis indicates the overall HR and the two vertical axes indicate its 95% CI. Every hollow round indicates the pooled HR when the left trial is omitted. The results of meta-regression with P-values are also displayed.