Caspian Journal of Internal Medicine

Background: The aim of this study was to evaluate the diagnostic accuracy of various non-invasive methods for Non-alcoholic fatty liver disease (NAFLD) diagnosis in an Iranian population. The methods studied included aspartate aminotransferase to platelet ratio index (APRI), fibrosis-4 (FIB-4) index, aspartate aminotransferase to alanine aminotransferase ratio (AAR), aspartate aminotransferase to platelet count index (AP index), fibrosis index (FI), NAFLD fibrosis score (NFS), Forns index, BARD score, BAAT score and PLALA score. The aim of the current study was to correlate these methods with liver stiffness measurement (LSM) and serum fibrosis markers, using FibroScan as the gold standard.
Methods: In a cross-sectional study of 504 patients with NAFLD or non-alcoholic steatohepatitis (NASH), FibroScan examinations were performed and demographic, clinical and biochemical data were collected. Statistical analyses evaluated the performance of each diagnostic panel, calculating sensitivity, specificity, positive predictive value, negative predictive value and accuracy.
Results: The APRI had high specificity (97.27%) but low sensitivity (4.12%) and limited discriminatory power AUC: 0.50) in the fibrosis panel. In contrast, Forns index and NFS had better AUC values (0.64 and 0.63, respectively), with the NFS having a sensitivity of 80%, indicating potential for broad-based screening. In the cirrhosis panel, the APRI was characterized by high specificity (98.21%) but had low sensitivity (4%) and limited discriminatory power (AUC: 0.51), while the FIB-4 had the highest AUC (0.67) and a sensitivity of 60%, suggesting its efficacy as a screening tool.
Conclusion: NFS and FIB-4 showed promising performance among the evaluated panels for population screening.