title: Accuracy of CT in the diagnosis of pulmonary embolism: a systematic literature review.
abstract: OBJECTIVE
  We sought to summarize systematically the published evidence describing the accuracy of contrast-enhanced helical CT for diagnosing pulmonary embolism.
  
  
  METHODS
  We selected all systematic reviews published before December 2003 that evaluated the accuracy of CT angiography for the diagnosis of pulmonary embolism. We also selected all prospective studies from the same time period in the primary literature in which all subjects underwent both CT and conventional angiography, the latter being considered the reference standard. Articles were identified through a computerized MEDLINE search and by other means. The quality and content of each article were evaluated independently by pairs of researchers.
  
  
  RESULTS
  Six systematic reviews and eight primary studies were selected. The combined sensitivities of CT for detecting pulmonary embolism ranged from 66% to 93% across the systematic reviews and the combined specificities ranged from 89% to 97%. Only one of the reviews reported a combined sensitivity of greater than 90%. Among the eight primary studies, the sensitivities ranged from 45% to 100% and specificities ranged from 78% to 100%. Only three of the eight primary studies reported a sensitivity greater than 90%. None of the primary studies used scanners with four or more detectors.
  
  
  CONCLUSIONS
  A systematic literature review revealed a wide range of reported sensitivities, only a minority of which exceeded 90%. Pooled estimates of sensitivity and specificity reported by systematic literature reviews should be interpreted with caution because of potential selection bias and heterogeneity in the reviewed studies. Accuracy studies of recent generations of MDCT scanners are not yet available despite the current dissemination of this technology.
authors.affiliation: Russell H. Morgan Department of Radiology and Radiological Science, Johns Hopkins University School of Medicine, 600 N Wolfe St., Central Radiology Viewing Area, Rm. 117, Baltimore, MD 21287, USA.
authors.forename: John
authors.initials: J
authors.lastname: Eng
authors.forename: Jerry A
authors.initials: JA
authors.lastname: Krishnan
authors.forename: Jodi B
authors.initials: JB
authors.lastname: Segal
authors.forename: Dennis T
authors.initials: DT
authors.lastname: Bolger
authors.forename: Leonardo J
authors.initials: LJ
authors.lastname: Tamariz
authors.forename: Michael B
authors.initials: MB
authors.lastname: Streiff
authors.forename: Mollie W
authors.initials: MW
authors.lastname: Jenckes
authors.forename: Eric B
authors.initials: EB
authors.lastname: Bass
mesh_terms: D006801:Humans; D011655:Pulmonary Embolism / Q000000981:diagnostic imaging*; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed