Figure 3. Receiver operating characteristic (ROC) curves for regucalcin (RGN) and alanine aminotransferase (ALT) in chronic hepatitis B (CHB) (A) and acute-on-chronic liver failure (ACLF) (B) patients. A, The area under the curve (AUC) for RGN was 0.86 with a cut-off of 2.42 ng/mL. The sensitivity and specificity were 85.7 and 78.8%, respectively. The AUC for ALT was 0.80 (95%CI: 0.70–0.89, P<0.01) with a cut-off of 28.30 U/L (sensitivity: 0.62 and specificity: 0.91), which is lower than the AUC for RGN (P=0.01). B, The AUC for RGN was 0.72 with a cut-off of 4.26 ng/mL. The sensitivity and specificity were 77.0 and 61.2%, respectively. In contrast, the AUC of ALT was only 0.41 (95%CI: 0.30–0.51, P=0.07) (P<0.01).