Search...

⌘K

Try AI Medical Scribe

Save 2+ hours daily with instant clinal dicumentation.

Start Free Trial

All tools /

Fibrosis-4 (FIB-4) Index for Liver Fibrosis

Fibrosis-4 (FIB-4) Index for Liver Fibrosis

Non-invasive estimate of liver fibrosis using routine labs

All tools /

Fibrosis-4 (FIB-4) Index for Liver Fibrosis

Fibrosis-4 (FIB-4) Index for Liver Fibrosis

Non-invasive estimate of liver fibrosis using routine labs

Age (years)
Patient's current age
AST (U/L)
Aspartate aminotransferase level
ALT (U/L)
Alanine aminotransferase level
Platelet Count (10⁹/L)
Number of platelets per liter
FIB-4 Index NaN — Advanced fibrosis likely (consider biopsy or imaging)
0/4 answered · tap options to update

Instructions

The Fibrosis-4 (FIB-4) Index is a non-invasive tool used to estimate the extent of liver fibrosis in patients with chronic liver disease, particularly viral hepatitis and fatty liver disease. The calculation uses four readily available clinical parameters: patient age, AST, ALT, and platelet count. By applying these values into the validated formula, the score helps identify patients at low, intermediate, or high risk for advanced fibrosis. This tool supports clinical decision-making by guiding whether patients need further imaging, non-invasive testing, or referral for biopsy.

Overview
When to use
Why use
Evidences

Interpretation

FIB-4 Score

Fibrosis Stage

< 1.45

0-1

1.45 – 3.25

2-3

> 3.25

4-6

 

FIB-4 was developed in HIV/HCV-coinfected adults as a simple noninvasive fibrosis index: FIB-4 = (Age×AST) / (Platelets×√ALT). It discriminated significant fibrosis with AUROC≈0.77 in derivation, proposing low and high cutoffs to rule out or in advanced fibrosis
https://pubmed.ncbi.nlm.nih.gov/16729309/

In 847 biopsies, FIB-4 <1.45 had NPV 94.7% for excluding severe fibrosis (F3–F4) and FIB-4 >3.25 had PPV 82.1% for confirming F3–F4; AUROC 0.85 for severe fibrosis and 0.91 for cirrhosis, correctly classifying 72.8% of cases
https://pubmed.ncbi.nlm.nih.gov/17567829/ 

A 2024 diagnostic meta-analysis in NAFLD, including high-prevalence T2DM cohorts, found low cutoffs (1.3–1.67) yield pooled sensitivity≈0.74 and specificity≈0.60 for advanced fibrosis; high cutoffs (2.67–3.25) had sensitivity≈0.33 and specificity≈0.92 with DOR reflecting strong rule-in utility but limited sensitivity
https://pmc.ncbi.nlm.nih.gov/articles/PMC11493353/

AASLD NAFLD guidance endorses FIB-4 as the initial risk stratifier in primary care/endocrinology, with thresholds such as <1.3 to defer further testing, 1.3–2.67 to proceed to elastography/ELF, and >2.67 to refer for specialist assessment and staging

https://pmc.ncbi.nlm.nih.gov/articles/PMC10735173/

Overview
When to use
Why use
Evidences

The FIB-4 Index is widely applied in hepatology as a simple, cost-effective, and non-invasive alternative to liver biopsy. It was initially developed for patients with hepatitis C but has since been validated across multiple liver conditions including hepatitis B, alcoholic liver disease, and nonalcoholic fatty liver disease (NAFLD).

The score helps distinguish between minimal and advanced fibrosis, enabling better patient stratification. A low score generally rules out advanced fibrosis, while a high score indicates the need for further evaluation or specialist referral. Intermediate values often warrant additional testing with elastography or other non-invasive markers.

Because it uses routine laboratory tests, FIB-4 is easily integrated into primary care and hepatology practice. This broad applicability makes it a valuable first-line screening tool to help reduce unnecessary invasive procedures, monitor progression of liver disease, and guide treatment decisions.

Overview
When to use
Why use
Evidences

Interpretation

FIB-4 Score

Fibrosis Stage

< 1.45

0-1

1.45 – 3.25

2-3

> 3.25

4-6

 

FIB-4 was developed in HIV/HCV-coinfected adults as a simple noninvasive fibrosis index: FIB-4 = (Age×AST) / (Platelets×√ALT). It discriminated significant fibrosis with AUROC≈0.77 in derivation, proposing low and high cutoffs to rule out or in advanced fibrosis
https://pubmed.ncbi.nlm.nih.gov/16729309/

In 847 biopsies, FIB-4 <1.45 had NPV 94.7% for excluding severe fibrosis (F3–F4) and FIB-4 >3.25 had PPV 82.1% for confirming F3–F4; AUROC 0.85 for severe fibrosis and 0.91 for cirrhosis, correctly classifying 72.8% of cases
https://pubmed.ncbi.nlm.nih.gov/17567829/ 

A 2024 diagnostic meta-analysis in NAFLD, including high-prevalence T2DM cohorts, found low cutoffs (1.3–1.67) yield pooled sensitivity≈0.74 and specificity≈0.60 for advanced fibrosis; high cutoffs (2.67–3.25) had sensitivity≈0.33 and specificity≈0.92 with DOR reflecting strong rule-in utility but limited sensitivity
https://pmc.ncbi.nlm.nih.gov/articles/PMC11493353/

AASLD NAFLD guidance endorses FIB-4 as the initial risk stratifier in primary care/endocrinology, with thresholds such as <1.3 to defer further testing, 1.3–2.67 to proceed to elastography/ELF, and >2.67 to refer for specialist assessment and staging

https://pmc.ncbi.nlm.nih.gov/articles/PMC10735173/

Frequently Asked Questions

Features and Services FAQs

Discover the full range of features and services we offer and how to use them.

What clinical data are needed for FIB-4?+
Can FIB-4 replace a liver biopsy?+
Is FIB-4 reliable in all populations?+
What should be done with intermediate scores?+
Can FIB-4 be used for alcohol-related liver disease?+
How often should FIB-4 be repeated?+

Ready to Transform Your Practice?

Join thousands of clinicians saving hours daily with AI-powered documentation.

14-day free trial • No setup fees

Ready to Transform Your Practice?

Join thousands of clinicians saving hours daily with AI-powered documentation.

14-day free trial • No setup fees

Ready to Transform Your Practice?

Join thousands of clinicians saving hours daily with AI-powered documentation.

14-day free trial • No setup fees

DocScrib

AI-powered medical documentation platform revolutionizing clinical workflows through intelligent patient management and secure documentation.

Product

How It Works

Pricing

FAQ

Articles

Blog

Security

Support

Contact Support

Sales Inquiries

1-800-DOCSCRIB

Help Center

Comparisons

vs Soaper

vs Freed

vs ChartNote

vs NoteMD

vs Heidi

vs Nabla

vs Doximity

vs Suki

Legal

Privacy Policy

Terms of Service

Security & Compliance

Legal Inquiries

© 2025 DocScrib. All rights reserved.

Privacy

Terms

Security

DocScrib

AI-powered medical documentation platform revolutionizing clinical workflows through intelligent patient management and secure documentation.

Product

How It Works

Pricing

FAQ

Articles

Blog

Security

Support

Contact Support

Sales Inquiries

1-800-DOCSCRIB

Help Center

Comparisons

vs Soaper

vs Freed

vs ChartNote

vs NoteMD

vs Heidi

vs Nabla

vs Doximity

vs Suki

Legal

Privacy Policy

Terms of Service

Security & Compliance

Legal Inquiries

© 2025 DocScrib. All rights reserved.

Privacy

Terms

Security

DocScrib

AI-powered medical documentation platform revolutionizing clinical workflows through intelligent patient management and secure documentation.

Product

How It Works

Pricing

FAQ

Articles

Blog

Security

Support

Contact Support

Sales Inquiries

1-800-DOCSCRIB

Help Center

Comparisons

vs Soaper

vs Freed

vs ChartNote

vs NoteMD

vs Heidi

vs Nabla

vs Doximity

vs Suki

Legal

Privacy Policy

Terms of Service

Security & Compliance

Legal Inquiries

© 2025 DocScrib. All rights reserved.

Privacy

Terms

Security

Model for End-Stage Liver Disease (Combined MELD)