Changes in patient concentration and accessibility across 5 Pediatric Emergency Departments in Daegu, Korea

Background: The coronavirus disease 2019 (COVID-19) pandemic has substantially altered Pediatric Emergency Department (PED) utilization.However, longitudinal changes across multiple PEDs after major policy transitions remain unclear.Purpose: This study aimed to evaluate changes in utilization, patient distribution, accessibility to pediatric emergency care, and clinical characteristics across 5 participating PEDs in Daegu, Korea.Methods: This multicenter retrospective study analyzed 140,017 visits among patients aged <16 years between January 2019 and May 2023.Concentration was assessed using monthly institutional shares and the Herfindahl-Hirschman Index (HHI), while the segmented interrupted time-series regression incorporated the Prais-Winsten correction and seasonal terms.The door-to-emergency room (door-to-ER) distance was defined as the WGS84 geodesic distance between the residential administrativedong centroid and fixed coordinates of the visited PED.We also evaluated the Korean Triage and Acuity Scale (KTAS) score, proportion of ambulance arrivals, and Emergency Department length of stay.Results: Median monthly population-standardized visit rates were 580.9, 315.8, and 500.1/100,000child personmonths in the pre-COVID, COVID, and post-COVID periods, respectively (P<0.001); the post-COVID rate did not differ significantly from the pre-COVID rate after Bonferroni adjustment.Center D's share increased from 25.7% in the pre-COVID period to 44.4% in the post-COVID period.The HHI showed no immediate level change but increased in slope after May 2022 (β=0.00437/mo;95% confidence interval, 0.00072-0.00801;P=0.020).Median door-to-ER geodesic distance increased from 6.44 to 8.68 km, and visits originating ≥20 km away increased from 16.8% to 20.9%, with a more pronounced distance increase among Daegu residents.The proportion of KTAS level 3 visits increased from 44.9% to 60.5%, and that of KTAS levels 1-2 from 3.0% to 4.3%.Conclusion: These findings indicate patient redistribution across the 5 participating PEDs serving Daegu and Gyeongsangbuk-do.Visit volume recovered after the COVID period, whereas patient distribution became increasingly concentrated with longer door-to-ER distances and greater reliance on emergency medical services, suggesting reduced accessibility.