Purpose National Institute for Emergency Medicine (NIEM) was established as the national lead agency for emergency medicine in 2008 in Thailand. This study aimed to evaluate the longitudinal effect of establishing NIEM on emergency medical service (EMS) use and case fatalities among patients with severe trauma.

Method Data were extracted from Khon Kaen Hospital’s Injury Surveillance Database. The analysis included injured patients with an Injury Severity Score of >15, directly transferred to its emergency department between January 1997 and December 2021. Changes in formal EMS use, total EMS use, and in-hospital deaths were investigated using segmented regression analysis. The change point in 2008 divided the study period into two segments.

Result The proportion of formal EMS use among severely injured patients increased by approximately 1.5% annually before 2008, with a level change of 52.9 percentage point (pp) increases in 2008, and without a significant slope change. The total EMS use, including informal EMS, increased by approximately 3.4% annually before 2008, with a level change of 17.9 pp increase in 2008, and a significant slope change in the decreasing direction of the increasing trend. The proportion of in-hospital deaths showed no significant changes before 2008, with an increase of 8.0 pp in 2008, with significant slope change and decreasing trends after 2008.

Conclusions The trends indicated a significant increase in EMS use among patients with severe trauma after establishing NIEM in 2008, which reflects the integration of informal EMS units into the formal system. However, a reduction in fatalities in 2008 was not observed.

The authors have declared no competing interest.

None

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The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

This study was approved by the ethics committees of Khon Kaen Regional Hospital and Kanagawa University of Human Services

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Funding support: None

Conflict of interest: None declared

Ethical clearance: This study was approved by the ethics committees of Khon Kaen Regional Hospital and Kanagawa University of Human Services

Previous presentation: None

All data produced in the present work are contained in the manuscript.