The best-balanced cut-off level of GDF-15 that discriminates between chronic HCV patient with liver fibrosis and controls was 150 ng/L, at which sensitivity was 96.7%, specificity 98.2%, positive predictive value (PPV) 98.2%, negative predictive value (NPV) 96.7%, and the diagnostic efficiency was 97.6%, with an area under the curve (AUC) of 0.99 as shown in Fig. 5 and Table 5. This evidence concerns the gene GDF15 and Hepatic fibrosis.