Formula reviewed
Fibrosis 4 FIB 4 Calculator
FIB 4 index Explanation and Clinical Context The FIB 4 index is a noninvasive score that estimates the probability of advanced liver fibrosis using routinely available values including patient age AST ALT and platelet count. It is calculated as age in years multiplied by AST in U per L divided by platelet count in 10 to the power of 9 per L times the square root of ALT in U per L. Commonly used cutoffs are less than