title: The performance of two rapid quantitative D-dimer assays in 287 patients with clinically suspected pulmonary embolism.
abstract: BACKGROUND
  Objective tests are necessary for the diagnosis of pulmonary embolism (PE). D-dimer assays have been suggested as useful screening tests to exclude this diagnosis.
  
  
  OBJECTIVE
  To compare the diagnostic accuracy of two rapid quantitative D-dimers in patients with suspected pulmonary embolism.
  
  
  METHODS
  Plasma D-dimer levels were measured using two commercially available assays (Tinaquant and Vidas). A strict imaging protocol was used to arrive at a final diagnosis of PE or deep venous thrombosis (DVT).
  
  
  METHODS
  Multicenter study in six Dutch referral centers.
  
  
  METHODS
  A total of 287 in- and outpatients with clinically suspected pulmonary embolism.
  
  
  METHODS
  Diagnostic accuracy indices for the two assays were calculated and additional receiver-operated characteristics (ROC) analysis was performed.
  
  
  RESULTS
  Using the manufacturer's advised cutoff values, the sensitivity and specificity were 88% and 52% for Vidas and 82% and 61% for Tinaquant, respectively. These differences were statistically significant (McNemar, P < 0.0001). However, no statistical differences were found between the two assays using ROC analysis (AUC = 0.78 for both assays).
  
  
  CONCLUSIONS
  Both quantitative D-dimer tests had similar diagnostic accuracy; however, at the manufacturer's advised cutoff level, Vidas performed significantly better. Nevertheless, to safely exclude pulmonary embolism, D-dimer assays should be combined with other diagnostic tests.
authors.affiliation: Department of General Internal Medicine, Leiden University Medical Center, Leiden, The Netherlands. w.de_monye@lumc.nl
authors.forename: Wouter
authors.initials: W
authors.lastname: de Monyé
authors.forename: Bernd-Jan
authors.initials: BJ
authors.lastname: Sanson
authors.forename: Harry R
authors.initials: HR
authors.lastname: Büller
authors.forename: Peter M T
authors.initials: PM
authors.lastname: Pattynama
authors.forename: Menno V
authors.initials: MV
authors.lastname: Huisman
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D019281:Dimerization; D005260:Female; D006801:Humans; D008297:Male; D009426:Netherlands; D011655:Pulmonary Embolism / Q000175:diagnosis*; D012372:ROC Curve; D012680:Sensitivity and Specificity; D013997:Time Factors