Two teams, one mission: A study using EMS units in hospital triage during active-shooter and other mass-casualty events


  • Thomas Simons, MA
  • Anke Richter, PhD
  • Lauren Wollman, PhD



EMS, triage, mass-casualty events, hospital-response planning


Background: Recent mass-casualty events have exposed errors with common assumptions about response processes, notably triage and transport of patients. Response planners generally assume that the majority of patients from a mass-casualty event will have received some level of field triage and transport from the scene to the hospital will have been coordinated through on-scene incident command. When this is not the case, emergency response at the hospital is hampered as staff must be pulled to handle the influx of untriaged patients.

Objective: Determine whether the use of emergency medical service (EMS) field resources in hospital triage could enhance the overall response to active-shooter and other mass-casualty events.

Design: A proof of concept study was planned in conjunction with a regularly scheduled mass-casualty hospital exercise conducted by an urban level II trauma center in Utah. This was a cross-over study with triage initially performed by hospital staff, and at the midpoint of the exercise, triage was transferred to EMS field units. General performance was judged by exercise planners with limited additional data collection.

Results: EMS crews at the hospital significantly enhanced the efficiency and efficacy of the triage operation in both qualitative and quantitative assessment.

Conclusions: Hospital planners deemed the proof of concept exercise a success and are now experimenting with implementation of this alternate approach to triage. However, much additional work remains to fully implement this change in processes.

Author Biographies

Thomas Simons, MA

Firefighter/Paramedic, Salt Lake City Fire Department, Salt Lake City, Utah

Anke Richter, PhD

Professor, Defense Resources Management Institute, Naval Postgraduate School, Monterey, California

Lauren Wollman, PhD

Professor, Center for Homeland Defense and Security, Naval Postgraduate School, Monterey, California


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How to Cite

Simons, MA, T., A. Richter, PhD, and L. Wollman, PhD. “Two Teams, One Mission: A Study Using EMS Units in Hospital Triage During Active-Shooter and Other Mass-Casualty Events”. American Journal of Disaster Medicine, vol. 15, no. 1, Jan. 2020, pp. 33-41, doi:10.5055/ajdm.2020.0353.