title: Validation of the Emergency Severity Index (ESI) in self-referred patients in a European emergency department.
abstract: OBJECTIVE
  To validate the Emergency Severity Index (ESI) triage algorithm in predicting resource consumption and disposition by self-referred patients in a European emergency department.
  
  
  METHODS
  This was a prospective, observational cohort study using a convenience sample of self-referred emergency department patients >14 years of age presenting to a busy urban teaching hospital during a 39-day period (27 May-4 July 2001). Observed resource use was compared with resource utilisation predicted by the ESI. Outpatient referrals after discharge and hospitalisations were also recorded.
  
  
  RESULTS
  ESI levels were obtained in 1832/3703 (50%) self-referred patients, most of whom were in the less severe ESI-4 (n = 685, 37%) and ESI-5 (n = 983, 54%) categories. Use of resources was strongly associated with the triage level, rising from 15% in ESI-5 to 97% in ESI-2 patients. Specialty consultations and admissions also rose with increasing ESI severity. Only 5% of ESI-5 patients required consultation and <1% were admitted, whereas 85% of ESI-2 patients received a consultation and 56% were admitted, 26% to a critical care bed. Only 2% of the ESI-5 patients underwent blood tests, compared with 76% of the sicker ESI-2 patients. X rays were the most commonly used resource in patients triaged to ESI-4 and ESI-5.
  
  
  CONCLUSIONS
  The ESI triage category reliably predicts the severity of a patient's condition, as reflected by resource utilisation, consultations and admissions in a population of self-referred patients in a European emergency department. It clearly identifies patients who require minimal resources, or at most an x ray, and those unlikely to require admission.
authors.affiliation: Department of Anaesthesiology, Haukeland University Hospital, Bergen N-5021, Norway. jhwelshove@c2i.net
authors.forename: Jolande
authors.initials: J
authors.lastname: Elshove-Bolk
authors.forename: Francis
authors.initials: F
authors.lastname: Mencl
authors.forename: Bas T F
authors.initials: BT
authors.lastname: van Rijswijck
authors.forename: Maarten P
authors.initials: MP
authors.lastname: Simons
authors.forename: Arie B
authors.initials: AB
authors.lastname: van Vugt
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D003955:Diagnostic Tests, Routine / Q000706:statistics & numerical data; D004636:Emergency Service, Hospital; D005260:Female; D006295:Health Resources / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D009664:Norway; D010342:Patient Acceptance of Health Care; D010343:Patient Admission / Q000706:statistics & numerical data; D011446:Prospective Studies; D012017:Referral and Consultation; D012720:Severity of Illness Index; D014218:Triage