PTH and Marchiafava-Bignami disease: To evaluate the contributions of each individual features to the four classes of CKD-MBD, we also computed the Pearson and Spearman correlation coefficients between all the features with the CKDMBD-Cal, CKDMBD-Phos, CKDMBD-PTH and CKDMBD-Any, respectively (shown in Fig. 1-B, Fig. S1-B, Fig. 2 and Fig. S2).