Sterling et al reported the FIB-4 score for evaluating hepatic fibrosis in a patient coinfected with with chronic viral hepatitis C (HCV) and HIV. It was derived from the APRICOT database. It has been used to evaluate patients infected with HCV alone.



(1) age in years

(2) platelet count in 10^9/L

(3) AST in IU/L

(4) ALT in IU/L


FIB-4 score =

= (age) * (AST) / ((platelet count) * SQRT(ALT))



• The higher the score the greater the risk for significant fibrosis.

FIB-4 Score

Percent with F3-F4 Fibrosis

< 1.45


1.45 to 3.25


> 3.25




• Vallet-Pichard et al found the FIB-4 to be concordant with the FibroTest 92% of the time when the score was < 1.45 and 76% of the time when the score was > 3.25.

• The method of measuring the AST and ALT will affect performance.


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