Table 3.

Serum-based biomarkers of liver fibrosis in NAFLD

Algorithm	Formula/parameters	Number of NAFLD patients	AUROC/Sn/Sp/NPV/PPV
APRI[88]	(AST (U/L)/(AST upper limit of normal))/(platelet count (× 109/L) × 100)	145	0.67/27/89/84/37
FIB-4[88–90]	(age (years) × AST (U/L)) / ((platelet count (× 109/L)) × (ALT(U/L))1/2)	145 541 1038	0.86/85/65/95/36 0.80/52/90/–/– 0.85/84/69/–/–
NFS[88–90]	− 1.675 + 0.037 × age (years) + 0.094 × BMI (kg/m2) + 1.13 × impaired fasting glucose/diabetes (yes = 1, no = 0) + 0.99 × AST/ALT ratio – 0.013 × platelet count (× 109/L) – 0.66 × albumin (g/dL)	733 145 1038	0.82–0.88/77–82/71–77/88–93/52–56
BARD[89, 91, 92]	BMI ≥ 28: No = 0, Yes = 1; AST/ALT ratio ≥ 0.8: No = 0, Yes = 2; and diabetes: No = 0, Yes = 1	827 145 138 1038	0.81/–/–/–/– 0.77/89/44/95/27 0.67/51/77/81/45 0.76/74/66/–/–
ELF[93, 94]	2.2781 + 0.851 × ln [HA] (µg/L) + 10.751 × ln [P3NP] (µg/L) + 10.934 × ln [TIMP 1] (µg/L)	61 192	0.87/89/96/96/80 0.90/80/90/94/71
FibroMeter[95]	Platelets, prothrombin index, AST, α2-macroglobulin, hyaluronic acid, urea, age	383	0.89*/81*/84*/77*/86*
FibroTest[96]	Haptoglobin, α2-macroglobulin, apolipoprotein A1, GGT, bilirubin, age, gender	267	0.81/92/71/98/33

^*Values are for prediction of significant fibrosis. ALT, alanine aminotransferase; APRI, AST-to-platelet ratio index; AST, aspartate aminotransferase; AUROC, area under the receiver operating characteristic; BMI, body mass index; DM, diabetes mellitus; ELF, enhanced liver fibrosis; FIB-4, fibrosis-4 score; GGT, gamma glutamyltransferase; IFG, impaired fasting glycemia; MMP, matrix metalloproteinases; NAFLD, non-alcoholic fatty liver disease; NFS, non-alcoholic fatty liver disease fibrosis score; NPV, negative predictive value; P3NP, N-terminal peptide of procollagen III; PPV, positive predictive value; TIMP, tissue inhibitors of metalloproteinases