Impact of size and occupancy of hospital on the extent of ambulance

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TITLE: The impact of size and occupancy of hospital on the extent of ambulance diversion: Theory and evidence

SPEAKER: Sarang Deo
Kellogg School of Management
Northwestern University


Emergency department (ED) overcrowding and consequent ambulance diversion is one of the most pressing healthcare delivery problems in the US and many other developed countries including the UK. In this paper we develop a two-stage queuing model to study the impact of structural factors such as the size and utilization of the inpatient department and the size of the ED on ambulance diversion status of the ED. In the face of analytically intractability, we develop two approximations based on heavy traffic theory and derive appropriate measures of inpatient occupancy and ED size that are associated with the extent of ambulance diversion. We then test the key insights from the analysis of these approximations using cross-sectional data of hospitals from California. We find that one of our approximations provides a better description of the data than the other. We also try to fit an empirical model with raw measures of size and occupancy and find that it does not explain the data well thereby providing additional support for our theoretical results.

Speaker Bio: Sarang Deo joined Kellogg School of Management in 2007 after completing his PhD from UCLA Anderson School of Management. His primary research interest is application of operations management methods to design efficient and effective healthcare delivery systems. His current work focuses on issues in resource-poor countries (developing models for HIV treatment scale-up, studying the impact of patient load on quality of care) as well as the US (joint planning of HIV screening and treatment at the Veterans Administration, theoretical and empirical investigation into the causes of ambulance diversion).


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  • Created By:
    Anita Race
  • Created:
  • Modified By:
    Fletcher Moore
  • Modified:


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