Assessing Efficiency in a Static-Based 9-1-1 Ambulance Service: An Analysis of Operational Performance Metrics

Abstract

Objectives

This study sought to evaluate performance indicators to assist a static-based 9-1-1 agency in defining its response efficiency.

Methods

Initial assessment of three metrics—unit hour utilization (UHU), fractile response intervals, and level 0 frequency (occurrence when no ambulances are available to respond)—suggested the agency’s response over its four coverage zones was inefficient, so an operational change was implemented: an ambulance was relocated from one service area to another to improve the overall response productivity. A 2-year retrospective analysis was performed to determine the impact ambulance relocation had on the three targeted measurements.

Results

The operational change resulted in a statistically significant change in unit hour utilization, a non-significant increase in fractile response intervals, and a statistically significant reduction in level 0 frequency from pre- to post-operational change times.

Conclusions

These findings suggest a way to evaluate the efficiency of static-based ambulance deployment and potentially identify strategies for redeployment.

Acknowledgments

The researchers express their sincere appreciation to the Johnson County Joint Emergency Communication Center for granting essential access to data, without which this project would have been impossible. Special thanks are extended to Johnson County Ambulance Service for their invaluable support throughout the research effort. The authors also wish to convey their gratitude to members of the University of Iowa Department of Emergency Medicine research staff, with particular acknowledgement to Nicholas Mohr and Sydney Krispin, both of whom provided valuable guidance throughout this project.

Disclosure Statement

The authors report there are no competing interests to declare.

Declaration of Generative AI in Scientific Writing

The authors did not use a generative artificial intelligence (AI) tool or service to assist with preparation or editing of this work. The authors take full responsibility for the content of this publication.