FIGURE 2.

a) Partial least squares (PLS) score plot and b) corresponding loading plot of the 29 ¹H nuclear magnetic resonance (NMR) spectra of the training set. The first predictive x-axis discriminates the urine profiles according to the composite physiologic index (CPI) score. Four components were calculated (R²X=0.28, Q²=0.67). Wpls1: weights of the first PLS component. c) Values of R² and Q² after 500 permutation tests. d) Application of the calculated model to the eight one-dimensional (1D) NMR urine spectra and projection. The y-axis corresponds to the prediction axis (CPI) and the x-axis corresponds to the sample number. The projection of the 1D spectrum corresponds to the circle and is compared to the CPI value (cross). e) Projection of the eight 1D NMR urine spectra of the test set onto the model.