Diagnostic performance of serum biomarkers for predicting advanced fibrosis in all patients. Receiver operating characteristic (ROC) curves of serum biomarkers for the diagnosis of advanced fibrosis in all patients. AUROC (95% CI): 0.60 (0.51–0.70) for AAR, 0.84 (0.78–0.90) for APRI, 0.88 (0.83–0.93) for FIB-4, 0.90 (0.84–0.95) for Forns index. Advanced fibrosis was defined as histologic liver fibrosis ≥ F4 according to Ishak et al. [29] for viral chronic liver disease, and ≥F3 according to Brunt/Kleiner et al. for NAFLD [27,28]. AAR, AST to ALT ratio; APRI, AST to Platelet Ratio Index; Fib-4, fibrosis 4.