Agreement of Prehospital Severity Assignment: Comparisons among 3 Different Patient Assessment Tools in Urban Emergency Medical Service
Keywords:emergency medical dispatch, over-triage, under-triage, National Early Warning Scoressystem: NEWS, criteria based dispatch
Introduction: Emergency Medical Services (EMS) in Thailand are considered as multi-tiered response system providing medical care regarding the degrees of emergency and severity prioritization. Thus, effective triage tools are mandatory for efficient resource management to achieve productivity during pre-hospital emergencies and casualties.
Objectives: To compare the agreement and consistency in severity assignment between the standard in-hospital emergency severity index (ESI) and the pre-hospital assessment tools, including the phone triage with criteria-based dispatch protocol and the on-scene triage using the National Early Warning Score (NEWS).
Methods: This is a retrospective, descriptive study of EMS missions conducted by a single urban EMS center, Vajira Hospital. Data including phone triage medical dispatch codes, pre-hospital NEWS and ESI levels were collected and analyzed.
Results: A total of 950 EMS missions were evaluated, among which 93.6% were categorized as ‘red code’. The phone triage medical dispatch demonstrated the over-triage rate of 26.2% and the under-triage rate of only 1.7% with slight reliability (Kappa 0.165; p-value < 0.001) when compared to ESI levels, whereas the pre-hospital NEWS resulted in the under-triage rate of 47.8% with fair reliability (Kappa 0.344; p-value < 0.001).
Conclusion: For pre-hospital settings, the phone triage using medical dispatch codes provides more accurate severity assignment with optimal outcomes consistent with the international recommendations, whereas the NEWS seems to generate excessive undertriage rate.
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