Fig. 3

Funnel plot of menthol mouth rinsing studies included in this meta-analysis. Both highlighted studies were considered to potentially influence the effect sizes. Pink dots represent individual effect sizes. The central black line represents the observed main estimate of this meta-analysis, while the black dotted and dashed lines represent the 95 and 99% confidence intervals, respectively. The blue line represents the Egger’s regression line illustrating the influence and the direction of the effect of smaller studies (i.e. with higher standard error values) on the obtained effect sizes