Fig. 3
PLS-DA score plot and its corresponding response permutation test based on the differentially expressed metabolites between males and females in this study. A PLS-DA score plot of all the participants included two components with a R2X value of 0.516, R2Y value of 0.748, and Q2 value of 0.65, indicating the model was stable and reliable. B Response permutation test indicated the constructed PLS-DA model was not over-fitting (R2 = (0.0, 0.311), Q2 = (0.0, -0.237)). PLS-DA, partial least squares-discriminant analysis