title: ROC-analysis of detection performance by analogue and digital plain film systems in chest radiography.
abstract: OBJECTIVE
  To compare the performances of 4 imaging systems in the diagnostic radiology of the chest: an asymmetric screen-film combination (a-SFC); a conventional screen-film combination of speed class 200 (SFC); a screen-film combination of speed class 200 with an aluminium lung filter; and digital luminescence radiographs (DLR).
  
  
  METHODS
  Object detectability studies were carried out using an anthropomorphic chest phantom. The images were obtained under standard exposure conditions at 125 kVp. The detection performance of the various systems was evaluated by receiver operating characteristic (ROC) analysis on the basis of a total of 12,240 observations.
  
  
  RESULTS
  In the overall evaluation the a-SFC and the SFC plus lung filter received equally high ratings of 0.878+/-0.018 and 0.860+/-0.21, respectively (p>0.05). There was no significant difference between the 200-speed SFC and the storage phosphor radiographs. In the mediastinum all the tested systems were clearly superior to the 200-speed SFC (p<0.05) while in the lung fields the 200-speed SFC received a high rating of 0.866+/-0.026. The a-SFC had slight advantages over the SFC plus lung filter and the 2 digital imaging modes (p>0.05).
  
  
  CONCLUSIONS
  The a-SFC and the digital luminescence radiographs provide a significant gain in diagnostic information in the mediastinum without diminishing detail detectability in the lung fields and without additional radiation exposure.
authors.affiliation: Central Radiological Diagnostic Institute, University Hospital, Essen-Cologne, Germany.
authors.forename: R D
authors.initials: RD
authors.lastname: Müller
authors.forename: S
authors.initials: S
authors.lastname: Wähling
authors.forename: H
authors.initials: H
authors.lastname: Hirche
authors.forename: M
authors.initials: M
authors.lastname: Voss
authors.forename: C
authors.initials: C
authors.lastname: Blendl
authors.forename: C
authors.initials: C
authors.lastname: Gocke
authors.forename: P
authors.initials: P
authors.lastname: Gocke
authors.forename: B
authors.initials: B
authors.lastname: Buddenbrock
authors.forename: V
authors.initials: V
authors.lastname: John
authors.forename: R
authors.initials: R
authors.lastname: Wiebringhaus
authors.forename: B
authors.initials: B
authors.lastname: Turowski
mesh_terms: D005374:Filtration; D006801:Humans; D008171:Lung Diseases / Q000000981:diagnostic imaging; D019047:Phantoms, Imaging; D012372:ROC Curve; D011856:Radiographic Image Enhancement; D013902:Radiography, Thoracic / Q000295:instrumentation / Q000379:methods*; D012680:Sensitivity and Specificity; D014963:X-Ray Intensifying Screens