Emergency Department Utilization Patterns and Regional Disparities in Access to Care for Children With Complex Chronic Conditions in Korea: A Nationwide Analysis.

BACKGROUND: Children with complex chronic conditions (CCCs) require timely, resource-intensive emergency care, yet how they access emergency departments (EDs) across South Korea-and how access relates to outcomes-remains unclear. METHODS: We analyzed nationwide ED visits (ages 0-19) in the National Emergency Department Information System, 2016-2022. CCCs were identified using the Pediatric Complex Chronic Conditions Classification System v3. Travel distance was the Euclidean distance from the centroid of the residential area to the ED. For regional analyses, 29 emergency medical services (EMS) regions were consolidated into eight broader zones. The primary outcome was intensive care unit (ICU) admission or ED death. We estimated adjusted associations using multilevel logistic regression with a hospital random intercept and applied inverse probability of treatment weighting to balance EMS transport. RESULTS: Of 7.76 million pediatric ED visits, 149,306 (1.9%) involved CCCs. Compared with non-CCC visits, CCC visits had higher acuity (the Korean Triage Acuity Scale 1-2: 16.5% vs. 3.1%), longer travel (median 11.2 vs. 6.2 km), and higher rates of ICU admission (4.4% vs. 0.3%) and ED death (0.2% vs. 0.04%); EMS arrival was also more frequent (11.8% vs. 8.0%) (all P < 0.001). Access was highly concentrated: 47.9% of CCC ED visits occurred in Seoul, and 40.7% were seen at five high-volume Seoul EDs. In weighted multilevel models, longer travel was independently associated with adverse outcomes: adjusted odds ratios were 1.3 (95% confidence interval, 1.2-1.3) for 15-59.9 km, 1.6 (1.4-1.8) for 60-99.9 km, and 1.3 (1.1-1.5) for ≥ 100 km (all P < 0.001). Findings were robust to additional adjustment for individual CCC categories and domains. CONCLUSION: CCC-related ED visits are characterized by higher acuity, longer travel, and worse outcomes, with marked centralization in a few hospitals in the capital region. Travel burden is independently associated with ICU admission or ED death, underscoring the need to strengthen regional pediatric emergency capacity and coordination so medically complex children can receive timely, high-quality emergency care closer to home.