Health Care Management Science

, Volume 13, Issue 2, pp 124–136

Evaluating emergency medical service performance measures



The ultimate goal of emergency medical service systems is to save lives. However, most emergency medical service systems have performance measures for responding to 911 calls within a fixed timeframe (i.e., a response time threshold), rather than measures related to patient outcomes. These response time thresholds are used because they are easy to obtain and to understand. This paper proposes a methodology for evaluating the performance of response time thresholds in terms of resulting patient survival rates. A model that locates ambulances to optimize patient survival rates is used for base comparison. Results are illustrated using real-world data collected from Hanover County, Virginia. The results indicate that locating ambulances to maximize seven and eight min response time thresholds simultaneously maximize patient survival. Nine and 10 min response time thresholds result in more equitable patient outcomes, with improved patient survival rates in rural regions.


Discrete optimization Emergency medical service Patient outcomes Performance measures Health policy modeling 


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Copyright information

© Springer Science+Business Media, LLC 2009

Authors and Affiliations

  1. 1.Department of Statistical Sciences & Operations ResearchVirginia Commonwealth UniversityRichmondUSA
  2. 2.Department of Industrial EngineeringClemson UniversityClemsonUSA

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