Analysis and comparison between crash- and health-based emergency medical service response across Alabama

Introduction: Emergency Medical Services (EMS) can respond to multiple types of urgent requests from patients demanding urgent healthcare. The total time duration of EMS responding to those requests consists of multiple delays at several stages (e.g., response-to-scene, on-scene, transport). Additionally, the corresponding delay at each stage may correlate with different characteristics (e.g., number of crews/patients, signal priority, acuity). Furthermore, those characteristics can have diversified correlations with EMS response for different urgent requests.Methods: To capture the diversified correlations for crash-based and health-based EMS requests, this paper collected EMS call data (2018-2019) from the Alabama Department of Public Health and defined crash-based EMS responses as people who are injured in traffic crashes and healthbased EMS response as people who either have heart-related health issues or stroke. To account for unobserved heterogeneity due to limited available data, we use random parameter parametric survival models to explore potential varying correlations of the characteristics associated with delays at different stages for three EMS response types.Results: The results indicate that 108,304, 110,262, and 24,421 EMS responses were requested for traffic crashes, heart problems, and stroke, respectively. The modeling results show that at different stages of EMS responses, the characteristics and their associations with stage delays are diversified. For example, at stage 1, work-related illness or injury is positively correlated with delay for crash- and heart-based EMS responses, but it has a negative association with delay for stroke-based EMS response. Emergency Medical Dispatch (EMD) performed, the number of crews at stage 2, automated signal changing technology at stage 3, additional agency on-scene at stage 4, and stretcher usage at stage 5 are found to correlate with reduced delays at each corresponding stage. Conclusions: This study offers implications about how various EMS response characteristics impact the delay for three types of EMS response: crash-, heart-, and stroke-based. The findings on those key characteristics would help researchers as well as EMS response personnel better understand how they are associated with EMS delays at different stages.

Automated summary

This study explores the impact of various characteristics on the delay of emergency medical services (EMS) response for crash-based, heart-based, and stroke-based emergencies. The findings indicate that the correlations between characteristics and delays vary at different stages of EMS response. For example, work-related illness or injury is positively correlated with delay for crash- and heart-based EMS responses at stage 1, but negatively correlated with delay for stroke-based EMS responses.