You can calculate the Maddrey score for Alcoholic Hepatitis using two formulas. Both the discriminant function formula uses different measurement units. To find discriminant function for steroid therapy in a conventional way, subtract PTC (Control Time) from PTP (Prothrombin Time), and multiply with 4.6. Now add the obtained value with serum bilirubin(mg/dL). To find discriminant function in SI unit(metric), you should repeat the same process and divide the resultant value with 17.1.
Maddrey's discriminant function was invented by Maddrey and Boitnott. Discriminant function formula is used to find prognosis in alcoholic hepatitis. Values resulting above 32 percent are suggestive for a poor prognosis.