APRI
AST to platelet ratio index for fibrosis risk.
RESULT
APRI
What is APRI?
AST to platelet ratio index for fibrosis risk. APRI is intended for use in: Adults.
How to Use the APRI Calculator
- Enter AST in U/L.
- Enter AST upper limit of normal (lab-specific) in U/L. Defaults to 40 U/L if left blank
- Enter Platelet count in ×10⁹/L.
- Click Calculate to see your result and interpretation.
Formula & Version
This calculator uses formula version 1.0, last reviewed September 2026.
Clinical Considerations & Limitations
- Best validated in chronic hepatitis C — accuracy is lower in other liver disease etiologies.
References
- Wai CT et al., Hepatology 2003;38:518-526
Frequently Asked Questions
What is APRI?
AST to platelet ratio index for fibrosis risk.
Who is APRI intended for?
Adults. Always confirm applicability to your specific patient before use.
What are the limitations of APRI?
Best validated in chronic hepatitis C — accuracy is lower in other liver disease etiologies.
What formula or reference does APRI use?
Wai CT et al., Hepatology 2003;38:518-526
Is APRI a diagnosis?
No. APRI produces a score or estimate to support clinical decision-making — it is not a diagnosis and should be interpreted alongside full clinical judgement.
Medical Disclaimer: Medical calculators are provided for informational and educational purposes only. Results should not be used as a substitute for professional medical advice, diagnosis, or treatment. Always verify results with a qualified healthcare professional.
