The new Injury Severity Score and the evaluation of pediatric trauma

Background: To compare the effectiveness of the Injury Severity Score (ISS) and New Injury Severity Score (NISS) in predicting mortality in pediatric trauma patients. Methods: NISS, the sum of the squares of a patient's three highest Abbreviated Injury Scale scores (regardless of body region), were calculated for 9,151 patients treated at four regional pediatric trauma centers and compared with previously calculated ISS values. The power of the two scoring systems to predict mortality was gauged through comparison of misclassification rates, receiver operating characteristic curves, and Hosmer-Lemeshow goodness-of-fit statistics. Results: Although there were significant differences in mean NISS and ISS values for each hospital, differences in the predictive abilities of the two scoring systems were insignificant, even when analysis was restricted to the subgroup of patients with severe or penetrating injuries. Conclusion: The significant differences in the predictive abilities of the ISS and NISS reported in studies of adult trauma patients were not seen in this review of pediatric trauma patients.