title: Emergency department crowding: prioritising quantified crowding measures using a Delphi study.
abstract: OBJECTIVE
  Emergency department (ED) crowding has been associated with a number of negative health outcomes, including unnecessary deaths, increased waiting times and a decrease in care quality. Despite the seriousness of this issue, there is little agreement on appropriate crowding measures to assess crowding effects on ED operations. The objective of this study was to prioritise a list of quantified crowding measures that would assess the current state of a department.
  
  
  METHODS
  A three round Delphi study was conducted via email and an Internet based survey tool. The panel consisted of 40 professionals who had exposure to and expertise in crowding. Participants submitted quantified crowding measures which, through three rounds, were evaluated and ranked to assess participant agreement for inclusion.
  
  
  RESULTS
  The panel identified 27 measures of which eight (29.6%) reached consensus at the end of the study. These measures comprised: (1) ability of ambulances to offload; (2) patients who leave without being seen or treated; (3) time until triage; (4) ED occupancy rate; (5) patients' total length of stay in the ED; (6) time to see a physician; (7) ED boarding time; and (8) number of patients boarding in the ED.
  
  
  CONCLUSIONS
  This study resulted in the identification of eight quantified crowding measures, which present a comprehensive view of how crowding is affecting ED operations, and highlighted areas of concern. These quantified measures have the potential to make a considerable contribution to decision making by ED management and to provide a basis for learning across different departments.
authors.affiliation: Engineering Design Centre, Department of Engineering, University of Cambridge, Trumpington Street, Cambridge CB2 1PZ, UK. kb424@cam.ac.uk
authors.forename: Kathleen
authors.initials: K
authors.lastname: Beniuk
authors.forename: Adrian A
authors.initials: AA
authors.lastname: Boyle
authors.forename: P John
authors.initials: PJ
authors.lastname: Clarkson
mesh_terms: D001509:Bed Occupancy / Q000706:statistics & numerical data; D003441:Crowding; D003697:Delphi Technique; D004636:Emergency Service, Hospital / Q000458:organization & administration*; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data; D010343:Patient Admission; D011795:Surveys and Questionnaires; D017748:Time Management; D016312:Treatment Refusal / Q000706:statistics & numerical data