Partial residual plots of mitochondrial biomarkers correlating with L-GrAFT score in the multivariate regression model. (a) Area under the curve (AUC) of P-L control efficiency, beta value 0.73; (b) AUC of cytochrome c control efficiency, beta value −1.79, and (c) AUC of LEAK respiration, beta value −0.35. Solid dots represent partial residuals, the solid line the regression line of the multivariate model and the 95% confidence intervals are marked in grey.