title: Characteristics favouring a delayed disposition decision in the emergency department.
abstract: BACKGROUND
  The working hours of a hospital affects efficiency of care within the emergency department (ED). Understanding the influences on ED time intervals is crucial for process redesign to improve ED patient flow.
  
  
  OBJECTIVE
  To assess characteristics that affect patients' transit through an ED.
  
  
  METHODS
  Retrospective cohort study from 2004 to 2010 of 268 296 adult patients who presented to the ED of an urban tertiary-referral Australian teaching hospital.
  
  
  RESULTS
  After adjustment for Australasian Triage Scale (ATS) category, every decade increase in age meant patients spent an additional 2 min in the ED waiting to be seen (P < 0.001) and an extra 29-min receiving treatment (P < 0.001). For every additional 10 patients in the ED, the 'waiting time' (WT) phase duration increased by 20 min (P < 0.001) and the 'Assessment and Treatment Time' (ATT) phase duration increased by 26 min (P < 0.001). When patients arrived outside working hours, the WT phase duration increased by 20 min (P < 0.001). When seen outside working hours, the ATT phase duration increased by 34.5 min (P < 0.001).
  
  
  CONCLUSIONS
  Extrinsic to the patients themselves and in addition to ED overcrowding, the working hours of the hospital affected efficiency of care within the ED. Not only should the whole of the hospital be involved in improving efficient and safe transit of patients through an ED, but the whole of the day and every day of the week deserve attention.
authors.affiliation: School of Computer Science, Engineering and Mathematics, Flinders University, Adelaide, South Australia, Australia.
authors.forename: L
authors.initials: L
authors.lastname: Perimal-Lewis
authors.forename: P H
authors.initials: PH
authors.lastname: Hakendorf
authors.forename: C H
authors.initials: CH
authors.lastname: Thompson
mesh_terms: D000293:Adolescent; D000328:Adult; D001291:Attitude of Health Personnel; D001315:Australia; D015331:Cohort Studies; D003441:Crowding; D003657:Decision Making; D057210:Delayed Diagnosis / Q000706:statistics & numerical data; D004636:Emergency Service, Hospital / Q000458:organization & administration*; D004638:Emergency Treatment / Q000592:standards / Q000639:trends; D005260:Female; D006301:Health Services Needs and Demand; D006784:Hospitals, Teaching; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data*; D016014:Linear Models; D008297:Male; D015999:Multivariate Analysis; D010343:Patient Admission / Q000592:standards / Q000639:trends*; D012189:Retrospective Studies; D062606:Tertiary Care Centers; D013997:Time Factors; D014218:Triage / Q000379:methods*; D014505:Urban Population; D055815:Young Adult
keywords: emergency medicine; healthcare delivery; hospital administration; outcome and process assessment (healthcare); public hospital