A negative SimpliRED D-dimer assay result does not exclude the diagnosis of deep vein thrombosis or pulmonary embolus in emergency department patients

Ann Emerg Med. 2000 Feb;35(2):121-5. doi: 10.1016/s0196-0644(00)70130-2.


Study objective: To determine whether a negative SimpliRED D-dimer assay result excludes the diagnosis of deep vein thrombosis (DVT) or pulmonary embolus (PE) in emergency department patients.

Methods: This prospective, institutional review board-approved, clinical trial enrolled consecutive adult ED patients with the suspected diagnosis of venous thromboembolism (VTE) (DVT or PE). Initial ED evaluation included the SimpliRED D-dimer assay (American Diagnostica Inc, Greenwich, CT). Physicians were blinded to assay results. The diagnosis of DVT was made with positive findings on lower-extremity ultrasonography. PE was confirmed by a high-probability ventilation/perfusion (V/Q) scan, a positive pulmonary angiogram, or a positive finding on lower-extremity ultrasonography. A presumptive diagnosis of VTE was made in patients who had VTE at follow-up or unexplained death during the study period.

Results: One hundred ninety-eight patients were enrolled during the study period. Twenty-five patients were excluded from data analysis; 9 had no diagnostic testing and 16 were lost to follow-up. Of the 173 patients analyzed, 57 (33%) had VTE-16 of 48 evaluated for DVT and 41 of 125 for suspected PE. The SimpliRED assay had a sensitivity of 65% and a negative predictive value of 81% for detection of VTE. In patients evaluated for DVT alone, the sensitivity was 56% and the negative predictive value was 77%. For patients with suspected PE, the sensitivity and negative predictive value were 68% and 83%, respectively.

Conclusion: In contrast to earlier reports on the SimpliRED D-dimer assay, a negative result failed to exclude the diagnosis of VTE in our ED population.

Publication types

  • Clinical Trial
  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Angiography
  • Diagnosis, Differential
  • Emergency Service, Hospital
  • Female
  • Fibrin Fibrinogen Degradation Products / analysis*
  • Hemagglutination Tests
  • Humans
  • Male
  • Middle Aged
  • Predictive Value of Tests
  • Prospective Studies
  • Pulmonary Artery / diagnostic imaging
  • Pulmonary Embolism / blood
  • Pulmonary Embolism / diagnosis*
  • Pulmonary Embolism / diagnostic imaging
  • Sensitivity and Specificity
  • Ultrasonography
  • Venous Thrombosis / blood
  • Venous Thrombosis / diagnosis*
  • Venous Thrombosis / diagnostic imaging
  • Ventilation-Perfusion Ratio


  • Fibrin Fibrinogen Degradation Products