Emergency room overcrowding and ambulance diversion have been a significant problem worldwide and it became more apparent during the COVID-19 pandemic. In Japan, the Dedicated Emergency Physician (DEP) model has been associated with reduced transport time, but it is unclear whether this benefit persisted during the pandemic. We analyzed changes transport outcomes during the COVID-19 pandemic in Japanese regions with and without DEP hospitals in order to evaluate the effectiveness of the DEP model and to identify factors which could improve transport outcomes. Using nationwide data from January 2015 to December 2021, we analyzed three target areas: Urayasu-Ichikawa (DEP Group 1), Shonan-Fujisawa (DEP Group 2), and Ichinomiya-Toyota (Non-DEP Group 3). DEP Groups 1 and 2 contained DEP hospitals, while Non-DEP Group 3 was selected for comparable population size and strong pre-pandemic transport performance. To minimize the impact of regional variations in COVID-19 prevalence, we compared the changes in transport outcomes before and after the pandemic between the target areas and the nearby comparison areas. In total, there were 150,856 transports in Group 1, 186,965 in Group 2, and 516,655 in Group 3. In the target areas of Groups 2 and 3, transport time changes were significantly shorter by 2.016 and 0.606 minutes, respectively, compared with comparison areas. Moreover, these areas had significantly lower odds of transportation difficulty (Group 2: OR 0.131, 95% CI 0.110–0.157; Group 3: OR 0.086, 95% CI 0.066–0.112). We found that common characteristics of these areas were densely located large-scale hospitals and makeshift buildings for COVID-19 patients just next to large-scale hospitals. These findings suggest that DEP hospitals alone did not guarantee favorable transport outcomes during the pandemic. A sufficient number of large-scale hospitals and nearby temporary facilities may be crucial to maintaining effective emergency transport under pandemic conditions.

The authors have declared no competing interest.

The author(s) received no specific funding for this work.

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This study was approved by the Ethics Committee of the International University of Health and Welfare, Narita Hospital (24-Im-014 June 25, 2024). Informed consent was not required to conduct this study because it was an observational study without intervention, and the data did not include identifiable personal information.

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