RESUMEN
BACKGROUND/PURPOSE: Resource-based severity of injury (SOI) measures, such as the International Classification of Disease (ICD) Critical Care Severity Score (ICASS), may characterize traumatic burden better than standard mortality-based measures. The purpose of this study was to validate the ICASS in a representative national-level trauma cohort and compare SOI measures between children and adults. METHODS: The National Trauma Databank was used to derive (2008-12) and validate (2013-15) ICASS and ICD Injury Severity Scores (ICISS, standard mortality-based SOI measure). SOI metrics and outcomes were compared between pediatric, adult, and elderly age groups. Logistic regression modeling evaluated predictors of critical care resource utilization. RESULTS: Derivation and validation cohorts consisted of 3.90 and 1.97 million patients, respectively. ICASS strongly predicted actual critical care utilization (OR 1.04, 95% CI 1.04-1.04, p<0.0001). Mean ICASS was 24.4 for children and 33.0 for adults (ratio 0.74), indicating predicted critical care utilization in children was three-quarters that of adults. In contrast, predicted pediatric mortality was less than half that of adults. CONCLUSIONS: Mortality-based SOI measures underestimate pediatric burden of injury. This study validates ICASS and demonstrates that pediatric resource-based SOI is more similar to that of adults. ICASS is easily calculated without a trauma registry and complements mortality-based measures. Level of evidence III, retrospective comparative study.