Comparison of Mortality and Costs at Trauma and Nontrauma Centers for Minor and Moderately Severe Injuries in California

Study objective We examine differences in inpatient mortality and hospitalization costs at trauma and nontrauma centers for injuries of minor and moderate severity. Methods Inpatient data sets from the California Office of Statewide Health Planning and Development were analyzed for 2009 to 2011. The study population included patients younger than 85 years and admitted to general, acute care hospitals with a primary diagnosis of a minor or moderate injury. Minor injuries were defined as having a New Injury Severity Score less than 5 and moderate injuries as having a score of 5 to 15. Multivariate logistic regression and generalized linear model with log-link and γ distribution were used to estimate differences in adjusted inpatient mortality and costs. Results A total of 126,103 admissions with minor or moderate injury were included in the study population. The unadjusted mortality rate was 6.4 per 1,000 admissions (95% confidence interval [CI] 5.9 to 6.8). There was no significant difference found in mortality between trauma and nontrauma centers in unadjusted (odds ratio 1.2; 95% CI 0.97 to 1.48) or adjusted models (odds ratio 1.1; 95% CI 0.79 to 1.57). The average cost of a hospitalization was $13,465 (95% CI $12,733 to $14,198) and, after adjustment, was 33.1% higher at trauma centers compared with nontrauma centers (95% CI 16.9% to 51.6%). Conclusion For patients admitted to hospitals for minor and moderate injuries, hospitalization costs in this study population were higher at trauma centers than nontrauma centers, after adjustments for patient clinical-, demographic-, and hospital-level characteristics. Mortality was a rare event in the study population and did not significantly differ between trauma and nontrauma centers.