Validity of Korean Triage and Acuity Scale for Predicting In-Hospital Mortality in Patients with Acute Traumatic Brain Injury : A Nationwide Population-Based Study of 2018-2020

OBJECTIVE: This study aimed to evaluate the clinical validity of the Korean triage and acuity scale (KTAS) in predicting in-hospital mortality and surgical intervention in patients with acute traumatic brain injury (TBI). METHODS: We conducted a retrospective cohort study using data from the National Emergency Department Information System (NEDIS) collected between January 2018 and December 2020. Patients aged ≥20 years with acute TBI (International Classification of Diseases, 10th revision [ICD-10] S06.1-S06.9) admitted through the emergency department (ED) within 24 hours of injury were included. Initial KTAS classification and modified KTAS after physician evaluation were analyzed. The primary endpoint was in-hospital mortality, and the secondary endpoint was the need for craniotomy or craniectomy. Predictive performance was assessed using logistic regression and receiver operating characteristic analysis. RESULTS: A total of 37450 patients were analyzed, with an overall in-hospital mortality of 11.5%. Craniotomy or craniectomy were performed in 9.8% of the TBI patients. Patients classified as initial KTAS level 1 had a 10.33-fold higher risk of in-hospital mortality (95% confidence interval [CI], 5.96-17.88) compared to those in level 5, while modified KTAS level 1 patients showed a 25.96-fold increased risk (95% CI, 6.37-105.76). The area under the curve (AUC) for in-hospital mortality was 0.750 for initial KTAS and 0.751 for modified KTAS, while the AUC for predicting surgical intervention was 0.666 for initial KTAS and 0.669 for modified KTAS. Retriage demonstrated the accuracy of the predictive validity of initial KTAS for in-hospital mortality. CONCLUSION: KTAS is an effective tool for early risk stratification in acute TBI, particularly for identifying critically ill patients. Retriage supplements the predictive validity of initial KTAS, supporting its role in guiding clinical decision-making. Further research is warranted to validate KTAS in broader TBI populations and refine its utility for surgical decision-making.