Survival tree and MELD to predict long term survival in liver transplantation waiting list.

MELD score is a formula based on laboratory variables used as a predictor of short-term mortality index in cirrhotic patients. It is applied to allocate patients in liver transplantation waiting list in many countries. However, MELD score cutoff point accuracy to predict long term mortality has not been statistically evaluated. The aim of this study was to analyze the MELD score and other variables related to long-term mortality using a new model: the Survival Tree analysis. The variables considered in this study were obtained at the time of liver transplantation list enrollment. The graphical representation of the survival trees showed that MELD 16 was the most statistically significant mortality cutoff point. The results were compatible with the MELD cutoff point reported in the clinical literature. This methodology can be extended to identify significant cutoff points related to other diseases whose severity is not necessarily expressed by MELD.