Table 2.
Predictive models for liver fibrosis based on serum markers
| Type | Equations | Primary study population |
|---|---|---|
| Based on indirect markers | ||
| AAR [14,15] | AST [IU/L]/ALT [IU/L] | Chronic hepatitis C |
| Nonalcoholic fatty liver disease | ||
| APRI [16,18] | (AST [IU/L]/(AST ULN [IU/L])/Platelet count [109/L]×100 | Chronic hepatitis C |
| Nonalcoholic fatty liver disease | ||
| BARD score [10] | AST/ALT ratio ≥0.8=2 points, weighted sum of BMI ≥28 [kg/m2]=1 point, T2DM=1 point | Nonalcoholic fatty liver disease |
| FIB-4 [11] | Age [years]×AST [IU/L]/(Platelet count [109/L]×) | Coinfection with hepatitis C virus and human immunodeficiency virus |
| NFS [12] | –1.675+0.037×age [years]+0.094×BMI [kg/m2]+1.13×IFG or T2DM (yes=1, no=0)+0.99×AST/ALT ratio–0.013×Platelet count [109/L]–0.66×serum albumin [g/dL] | Nonalcoholic fatty liver disease |
| Forns index [13] | 7.811–3.131×ln(Platelet count [109/L])+0.781×ln(GGT[IU/L])+3.467×ln(age [years])–0.014×cholesterol [mg/dL] | Chronic hepatitis C |
| Based upon direct markers | ||
| ELF [3] | –7.412+0.681×ln(HA)+0.775×ln(PIIINP)+0.494×ln(TIMP1) | Chronic hepatitis C |
| FibroTest [30,32] | Patented algorithm combining total bilirubin, GGT, α2-macroglobulin, apolipoprotein A1, and haptoglobin, corrected for age and sex | Chronic hepatitis C |
| ADAPT [27] | exp (log10 ((age [years]×PRO-C3 [ng/mL])/))+T2DM (yes=1, no=0) | Nonalcoholic fatty liver disease |
| FIBC3 [28] | –5.939+0.053×age [years]+0.076×BMI [kg/m2]+1.614×T2DM (yes=1, no=0) –0.009×Platelet count [109/L]+0.071×PRO-C3 [ng/mL] | Nonalcoholic fatty liver disease |
| NIS4 [24] | ey/(1+ey), where y=β0+β1×log10(miR-34a-5p [Fold])+β2×α2-macroglobulin [g/L])+β3×(YKL-40 [ng/mL])+β4×(HbA1c [%]) | Nonalcoholic fatty liver disease |
| NIS2+ [31] | ey/(1+ey), where y=β0+β1×log10(miR-34a-5p [Fold])+β0×log10(YKL-40 [ng/mL])+β3×sex (female=0, male=1)+β4×log10(miR-34a-5p [Fold])×sex (female=0, male=1) | Nonalcoholic fatty liver disease |
AAR, AST/ALT ratio; AST, aspartate aminotransferase; ALT, alanine aminotransferase; APRI, AST-to-platelet ratio index; ULN, upper limit of normal; BMI, body mass index; T2DM, type 2 diabetes mellitus; NFS, nonalcoholic fatty liver disease fibrosis score; IFG, impaired fasting glucose; GGT, gamma-glutamyl transpeptidase; ELF, enhanced liver fibrosis; HA, hyaluronic acid; PIIINP, N-terminal peptide of pro-collagen III; TIMP1, tissue inhibitor of metalloproteinase 1; PRO-C3, pro-collagen 3 neoepitope; HbA1c, glycated hemoglobin.
Beta coefficients of NIS2+ and NIS4 are not the same.