The generalizability of the Mayo model for predicting survival in individual primary biliary cirrhosis patients without liver transplantation was tested and confirmed. The model was applied to a data base of patients from the New England Medical Center Hospitals (n = 141) and the Scott and White Clinic (n = 35) and found to predict their survival accurately. It was also shown to be accurate for Mayo primary biliary cirrhosis patients with very advanced disease (n = 30), those with less than a 33% chance of surviving 12 months. The analyses confirmed that the addition of histologic stage did not significantly improve the predictive power of the model (p greater than 0.10). We suggest that the Mayo model is a practical tool for clinical management and decision making.