Factors Associated with the Misclassification of a New Triage Tool in Pediatric Emergency Departments in Korea: A Nationwide Retrospective Observational Study

Background: This study aimed to investigate the factors affecting mistriage,including overtriage and undertriage, associated with the use of a new triage tool for assessing patient urgency in pediatric emergency departments (PEDs). Methods: This was a retrospective observational study based on the national registry data of patients aged < 15 years who visited PEDs between January 2016 and December 2019. Patients were classified into non-mistriage, overtriage, and undertriage groups, and the incidence and risk factors of mistriage and its characteristics according to hospital size were analyzed. Results: Overall, 5,462,964 patients were included, of whom 129,903 (2.4%) were excluded. Overtriage and undertriage occurred in 35,897 (0.7%) and 94,006 (1.7%) patients, respectively. The overtriage-associated factors were age of 1–4 years, female sex, evening visits, night, disease group, and self-referrals. The undertriage-associated factors were age of <1 year, male, daytime visits, trauma group, and referral from a clinic or outpatient department. There were also differences in the tendency for mistriage according to hospital size. Conclusion: This study identified major risk factors related to mistriage in patients in PEDs. Accurate triage that considers these factors is essential for providing appropriate treatment and efficient use of PED resources.