title: The impact of radiologists' expertise on screen results decisions in a CT lung cancer screening trial.
abstract: OBJECTIVE
  To evaluate the impact of radiological expertise on screen result decisions in a CT lung cancer screening trial.
  
  
  METHODS
  In the NELSON lung cancer screening trial, the baseline CT result was based on the largest lung nodule's volume. The protocol allowed radiologists to manually adjust screen results in cases of high suspicion of benign or malignant nodule nature. Participants whose baseline CT result was based on a solid or part-solid nodule were included in this study. Adjustments by radiologists at baseline were evaluated. Histology was the reference for diagnosis or to confirm benignity and stability on subsequent CT examinations.
  
  
  RESULTS
  A total of 3,318 participants (2,796 male, median age 58.0 years) were included. In 195 participants (5.9 %) the initial baseline screen result was adjusted by the radiologist. Adjustment was downwards from positive or indeterminate to negative in two and 119 participants, respectively, and from positive to indeterminate in 65 participants. None of these nodules turned out to be malignant. In 9/195 participants (4.6 %) the screen result was adjusted upwards from negative to indeterminate or indeterminate to positive; two nodules were malignant.
  
  
  CONCLUSIONS
  In one in 20 cases of baseline lung cancer screening, nodules were reclassified by the radiologist, leading to a reduction of false-positive screen results.
authors.affiliation: Center for Medical Imaging - North East Netherlands, University of Groningen, University Medical Center Groningen, Hanzeplein 1, 9713 GZ, Groningen, The Netherlands.
authors.forename: Marjolein A
authors.initials: MA
authors.lastname: Heuvelmans
authors.forename: Matthijs
authors.initials: M
authors.lastname: Oudkerk
authors.forename: Pim A
authors.initials: PA
authors.lastname: de Jong
authors.forename: Willem P
authors.initials: WP
authors.lastname: Mali
authors.forename: Harry J M
authors.initials: HJ
authors.lastname: Groen
authors.forename: Rozemarijn
authors.initials: R
authors.lastname: Vliegenthart
mesh_terms: D000368:Aged; D002983:Clinical Competence / Q000592:standards*; D055088:Early Detection of Cancer / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000000981:diagnostic imaging* / Q000473:pathology; D008297:Male; D008875:Middle Aged; D009929:Organ Size; D011871:Radiology / Q000592:standards*; D003074:Solitary Pulmonary Nodule / Q000000981:diagnostic imaging / Q000473:pathology; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000592:standards*