Medical utilization of patients encountering traffic accidents according to injury severity based on nationwide automobile insurance data in Korea

Research Objectives This study explored the characteristics of medical care utilization in patients encountering traffic accidents according to injury severity. Design Retrospective cohort study. Setting Population-based study. Participants Patients claiming automobile insurance due to a traffic accident between 2014 and 2019 were included in the study (n=11,476,597). Patients without medical institution information after a traffic accident were excluded (n=5). Interventions This was an observational study. Main Outcome Measures The main outcome of this study was the severity of injury caused by traffic accidents. We reviewed automobile insurance data from the Health Insurance Review & Assessment Service between 2014 and 2019. Patients with traumatic injuries were identified using the International Classification of Diseases, 10th revision (S or T codes). Injury severity was defined using an Excess Mortality Ratio-adjusted Injury Severity Score (EMR-ISS). Injury severity was classified as mild (EMR-ISS ≤ 8), moderate (9 ≤ EMR-ISS ≤ 24), or severe (EMR-ISS ≤ 24). Results Between 2014 and 2019, the proportion of mild injuries was the highest, followed by moderate and severe injuries. The age- and sex-adjusted incidence of traffic accidents increased significantly (34.4 per 1,000 cases in 2014; 42.0 per 1,000 cases in 2019). After stratification according to severity, only the incidence of mild injuries were found to increase significantly. The use of Korean medicine hospitals by all patients encountering traffic accidents increased significantly from 3.5% in 2014 to 14.2% in 2019; particularly, the use of Korean medicine hospitals increased most rapidly in patients with mild injuries. From 2014 to 2019, although the proportion of inpatient care for patients encountering traffic accidents gradually decreased, the median total medical costs increased, while the median length of stay remained constant. Conclusions Patients encountering traffic accidents presented different characteristics of medical utilization according to the severity of injury. Our findings can contribute to the development of strategies for providing medical services tailored to the severity of patients encountering traffic accidents. Author(s) Disclosures This study was supported by a grant from the Ministry of Land, Infrastructure and Transport (MOLIT) Research Fund (NTRH RF-2023001).