title: Prediction of bacteremia in the emergency department: an external validation of a clinical decision rule.
abstract: OBJECTIVE
  The objective of this study was to validate a previously published clinical decision rule for predicting a positive blood culture in emergency department (ED) patients with suspected infection on the basis of major and minor criteria and a total score (Shapiro et al., J Emerg Med, 2008; 35:255-264).
  
  
  METHODS
  This is a retrospective matched cohort study of adult ED patients with blood cultures obtained from 1 January 2011 through to 31 December 2011. ED patients with blood culture-confirmed bacteremia were matched 1 : 3 with patients with negative cultures. The outcome was 'true bacteremia'. Data on clinical history, comorbid illnesses, physical observations, and laboratory tests were used to evaluate the application of the clinical decision rule. We report the sensitivity, specificity, and area under the curve.
  
  
  RESULTS
  Among 1526 patients, 105 (6.9%) patients were classified with true bacteremia. The sensitivity of the prediction rule was 94% (95% confidence interval, 88-98%) and the specificity was 48% (95% confidence interval, 42-53%). The area under the receiver-operating characteristics curve was 0.83.
  
  
  CONCLUSIONS
  The clinical decision rule performed well in our ED setting and is likely to be a useful supplement to clinical judgment.
authors.affiliation: aResearch Center for Emergency Medicine Departments of bInfectious Diseases cClinical Microbiology, Aarhus University Hospital, Aarhus dDepartment of Clinical Microbiology, Aalborg University Hospital, Aalborg, Denmark eDepartment of Emergency Medicine, Beth Israel Deaconess Medical Center, Boston, Massachusetts, USA.
authors.forename: Marie K
authors.initials: MK
authors.lastname: Jessen
authors.forename: Julie
authors.initials: J
authors.lastname: Mackenhauer
authors.forename: Anne Mette S W
authors.initials: AM
authors.lastname: Hvass
authors.forename: Svend
authors.initials: S
authors.lastname: Ellermann-Eriksen
authors.forename: Simon
authors.initials: S
authors.lastname: Skibsted
authors.forename: Hans
authors.initials: H
authors.lastname: Kirkegaard
authors.forename: Henrik C
authors.initials: HC
authors.lastname: Schønheyder
authors.forename: Nathan I
authors.initials: NI
authors.lastname: Shapiro
mesh_terms: D000328:Adult; D000368:Aged; D016470:Bacteremia / Q000097:blood* / Q000453:epidemiology / Q000503:physiopathology; D001769:Blood / Q000382:microbiology*; D017848:Blood-Borne Pathogens / Q000302:isolation & purification*; D016022:Case-Control Studies; D016009:Chi-Square Distribution; D016208:Databases, Factual; D020000:Decision Support Systems, Clinical; D003718:Denmark; D004636:Emergency Service, Hospital; D005260:Female; D006785:Hospitals, University; D006801:Humans; D008297:Male; D008875:Middle Aged; D017063:Outcome Assessment, Health Care; D011237:Predictive Value of Tests; D012372:ROC Curve; D012189:Retrospective Studies; D018709:Statistics, Nonparametric