A conceptual model of emergency department crowding

Ann Emerg Med. 2003 Aug;42(2):173-80. doi: 10.1067/mem.2003.302.


Emergency department (ED) crowding has become a major barrier to receiving timely emergency care in the United States. Despite widespread recognition of the problem, the research and policy agendas needed to understand and address ED crowding are just beginning to unfold. We present a conceptual model of ED crowding to help researchers, administrators, and policymakers understand its causes and develop potential solutions. The conceptual model partitions ED crowding into 3 interdependent components: input, throughput, and output. These components exist within an acute care system that is characterized by the delivery of unscheduled care. The goal of the conceptual model is to provide a practical framework on which an organized research, policy, and operations management agenda can be based to alleviate ED crowding.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Acute Disease / therapy
  • Bed Occupancy / statistics & numerical data
  • Crowding*
  • Efficiency, Organizational
  • Emergency Service, Hospital / organization & administration*
  • Health Planning / organization & administration
  • Health Policy
  • Health Services Accessibility / organization & administration
  • Health Services Research
  • Length of Stay / statistics & numerical data
  • Models, Organizational*
  • Needs Assessment / organization & administration
  • Operations Research
  • Outcome and Process Assessment, Health Care / organization & administration
  • Patient Admission / statistics & numerical data
  • Patient Discharge / statistics & numerical data
  • Research Design
  • Total Quality Management / organization & administration
  • Triage / organization & administration
  • United States