We analyzed the accuracy of TRISS and a revised TRISS to predict survival outcome in a group of 1,562 consecutive children less than 15 years old admitted with blunt trauma to a pediatric trauma center. TRISS is an index that computes a probability of survival for each patient based on Trauma Score, Injury Severity Score, and age. R-TRISS uses the Revised Trauma Score instead of the Trauma Score. We used a statistical method based on TRISS and R-TRISS to compare patient outcomes from the pediatric study group with those of an adult baseline control group from the Major Trauma Outcome Study. Both TRISS and R-TRISS have the capability to accurately quantify survival outcome for children with blunt trauma; there was no statistical difference between the two methods to do so.