title: Comparison of two clinical scoring systems for emergency department risk stratification of suspected acute coronary syndrome.
abstract: OBJECTIVE
  To compare two methods of risk stratification for suspected acute coronary syndrome (ACS) in the ED.
  
  
  METHODS
  A prospective observational multicentre study was undertaken of patients undergoing evaluation in the ED for possible ACS. We compared the National Heart Foundation of Australia/Cardiac Society of Australia and New Zealand (NHF/CSANZ) guideline and the Thrombolysis in Myocardial Infarction (TIMI) risk score for differentiating high- and low-risk patients. Composite outcome was all cause death, myocardial infarction or coronary revascularisation within 30 days.
  
  
  RESULTS
  Of 1758 enrolments, 223 (13%) reached the study outcome. Area under the receiver operator characteristic (ROC) curve was 0.79 (95% CI 0.76-0.81) for the NHF/CSANZ group and 0.71 (0.68-0.75) for TIMI score based on initial troponin result (P<0.001), and 0.82 (95% CI 0.80-0.84) and 0.76 (0.73-0.79) respectively when the 8-12 h troponin result is included (P=0.001). Thirty day event rates were 33% for NHF/CSANZ high-risk vs 1.5% for combined low/intermediate risk (P<0.001). For TIMI score, 30 day event rates were 23% for a score ≥2 and 4.8% for TIMI<2 (P<0.001). The NHF/CSANZ guideline identified more patients as low risk compared with the TIMI risk score (61% vs 48%, P<0.001).
  
  
  CONCLUSIONS
  The NHF/CSANZ guideline is superior to the TIMI risk score for risk stratification of suspected ACS in the ED.
authors.affiliation: Emergency Department, Armadale Health Service, Western Australia, Australia. stephen.macdonald@health.wa.gov.au
authors.forename: Stephen P J
authors.initials: SP
authors.lastname: Macdonald
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Nagree
authors.forename: Daniel M
authors.initials: DM
authors.lastname: Fatovich
authors.forename: Helen L
authors.initials: HL
authors.lastname: Flavell
authors.forename: Francis
authors.initials: F
authors.lastname: Loutsky
mesh_terms: D054058:Acute Coronary Syndrome / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D000368:Aged; D001315:Australia; D015415:Biomarkers / Q000097:blood; D004562:Electrocardiography; D004636:Emergency Service, Hospital; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009203:Myocardial Infarction / Q000175:diagnosis* / Q000188:drug therapy / Q000503:physiopathology; D009520:New Zealand; D017410:Practice Guidelines as Topic; D011237:Predictive Value of Tests; D011446:Prospective Studies; D018570:Risk Assessment / Q000379:methods*; D012307:Risk Factors; D015912:Thrombolytic Therapy; D014336:Troponin / Q000097:blood
chemical_list: D015415:Biomarkers; D014336:Troponin