ENPP2 and Cirrhosis: Although there were no associations between Child-Pugh classes and ATX levels in cirrhotic patients (11.5 ± 3.5 vs. 12.1 ± 4.1 vs. 11.0 ± 2.0 nmol mL−1 min−1 in Child-Pugh stage A, B and C, respectively; P > 0.05 for all; Supplementary Figure 3A), the AUC analysis identified serum ATX activity as a significant predictor of cirrhosis (AUC = 0.7; 95%CI = 0.60–0.79; P < 0.001; Supplementary Figure 4A).