Hepatology Equation Strong evidence Clinical review pending v1.0.0

FIB-4 Index for Liver Fibrosis

Does this patient likely have advanced liver fibrosis?

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About this tool

Non-invasive fibrosis index from age, AST, ALT and platelets, with context- and age-specific cut-offs.

Intended use

Adults with MASLD/NAFLD or viral hepatitis, as a first-line fibrosis triage test.

Outcome

Advanced fibrosis (F3–F4)

Time horizon

Point in time

Derivation population

HIV/HCV coinfected patients (derivation); validated in NAFLD cohorts.

Limitations

Indeterminate results are common.
Less reliable under age 35 and in acute hepatitis.

Clinical problems

Liver disease

Evidence

Evidence level

Strong evidence

Derived and externally validated in multiple cohorts (including prospective studies) and incorporated into major clinical guidelines. Methodology

Guideline status

Recommended as the first-line fibrosis test in AASLD (2023) and EASL MASLD guidance.

Evidence summaries for this tool are awaiting independent clinical review. Statistics are shown only where they could be attributed to a specific publication.

References

Original publicationSterling RK, Lissen E, Clumeck N, et al. Development of a simple noninvasive index to predict significant fibrosis in patients with HIV/HCV coinfection. Hepatology 2006;43:1317-1325. Find on PubMed (opens in a new tab)
Validation studyShah AG, Lydecker A, Murray K, et al. Comparison of noninvasive markers of fibrosis in patients with nonalcoholic fatty liver disease. Clin Gastroenterol Hepatol 2009;7:1104-1112. Find on PubMed (opens in a new tab)
Validation studyMcPherson S, Hardy T, Dufour JF, et al. Age as a Confounding Factor for the Accurate Non-Invasive Diagnosis of Advanced NAFLD Fibrosis. Am J Gastroenterol 2017;112:740-751. Find on PubMed (opens in a new tab)

Version history

Version	Formula	Effective	Reviewer	Changes
v1.0.0	Sterling 2006; Shah 2009 / McPherson 2017 cut-offs	2026-10-03	—	Initial implementation with reference test vectors.

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Clinical decision support only. Interpret results in the context of the individual patient and current guidance; HumanPulse does not replace professional medical judgment.