title: The comparative analytical performance of four troponin I assays at low concentration.
abstract: BACKGROUND
  Low troponin concentrations have been shown to be informative in the prognosis of acute coronary syndrome. We have investigated the analytical performance of four commonly used cardiac troponin I methods at concentrations approaching their analytical limit of detection.
  
  
  METHODS
  We assayed 167 patient samples within 24 h of collection using the Beckman Coulter AccuTnI, Dade Behring Dimension, Abbott AxSYM and Bayer Centaur methods and compared their relative analytical performance.
  
  
  RESULTS
  Of the four assays compared, the AccuTnI was observed to have greater sensitivity at low concentrations. Using the limit of detection as the threshold, the Beckman assay showed superior performance at concentrations corresponding to a 20% coefficient of variation (CV), the Dade assay had a similar performance; and at concentrations corresponding to 10% CV most assays provide similar information.
  
  
  CONCLUSIONS
  The newer or recently modified assays such as the Beckman Coulter AccuTnI and Dade Behring assays are best able to identify very low concentrations of troponin.
authors.affiliation: Northside Pathology, The Prince Charles Hospital, Queensland Health Pathology Service, Brisbane, Australia. gus.koerbin@act.gov.au
authors.forename: G
authors.initials: G
authors.lastname: Koerbin
authors.forename: J R
authors.initials: JR
authors.lastname: Tate
authors.forename: J M
authors.initials: JM
authors.lastname: Potter
authors.forename: P E
authors.initials: PE
authors.lastname: Hickman
mesh_terms: D003937:Diagnosis, Differential; D006331:Heart Diseases / Q000097:blood* / Q000175:diagnosis*; D006801:Humans; D007118:Immunoassay; D011237:Predictive Value of Tests; D012016:Reference Values; D012680:Sensitivity and Specificity; D019210:Troponin I / Q000097:blood*
chemical_list: D019210:Troponin I