The International Normalized Ratio of Prothrombin Time in the Model for End-Stage Liver Disease Score: A Reliable Measure

The Model for End-stage Liver Disease (MELD) has been demonstrated to be an excellent predictor of survival in patients who have end-stage liver disease. It is derived from the international normalized ratio (INR) of prothrombin time, serum creatinine, and serum total bilirubin. The major use of the MELD score is to prioritize allocation of organs for liver transplant among patients who have chronic liver disease. Virtually every study that has looked at the MELD score as a predictor of survival has demonstrated that the MELD score using the INR with international sensitivity index calibrated for patients on warfarin has a 'c' statistic of approximately 0.8, indicating excellent discrimination.