Fig 9. Funnel plot effect sizes Nordic hamstring exercise on biceps femoris fascicle length based on the ultrasound assessment and extrapolation methods.

Red coloured squares represent studies that used manual linear extrapolation method, black coloured circles represent studies that used panoramic ultrasound scanning method, and green coloured squares represent studies that used trigonometric equation method. The asymmetry in the figure means a publication bias between the study groups that were used different ultrasound assessment methods (created via RevMan 5.4.1). Acronyms: SE(SMD), standard error of standardised mean differences; SMD, standardised mean difference.