Child-Pugh Score

Thresholds: bilirubin 34.2 and 51.3 µmol/L (2 and 3 mg/dL), albumin 35 and 28 g/L (3.5 and 2.8 g/dL), INR 1.7 and 2.3. Two of the five parameters — ascites and encephalopathy — are graded by judgement rather than measured, so the same patient can move a point or two between assessors.

INR replaces Pugh's original variable.The 1973 paper scored prothrombin time in seconds prolonged (<4, 4–6, >6). INR is the modern substitution and what laboratories report, so it is what this form asks for.

It was not designed for drug dosing. The score was built to predict mortality in cirrhotic patients undergoing portocaval surgery. It is widely used to band hepatic impairment on drug labels, but there is no validated scoring system for medication dosing in cirrhosis — combine it with the individual patient.

In primary biliary cholangitis and primary sclerosing cholangitis, higher bilirubin cut points are conventionally used, because cholestasis raises bilirubin without the same loss of synthetic function. This form uses the standard thresholds.