title: Nonradiologists as second readers for intraluminal findings at CT colonography.
abstract: OBJECTIVE
  Multiple trials have documented wide interobserver variability between radiologists interpreting computed tomography colonography (CTC) exams. We sought to determine if nonradiologists could learn to interpret intraluminal findings at CTC with a high degree of sensitivity to determine if they could play a role as second readers in interpreting CTC exams.
  
  
  METHODS
  Seven nonradiologists (five medical students, two radiologic technologists) undertook self-directed CTC training using a teaching file of 50 cases; thereafter, each reader blindly interpreted 50 cases with colonoscopic correlation (30 positive, 20 negative). Results were compared with a previously studied cohort of radiologists. The two technologists additionally repeated the exam after 6 weeks of clinical experience.
  
  
  RESULTS
  The sensitivity of nonradiologists for small (5-9 mm) polyps, large (>9 mm) lesions, and cancers was similar to that of radiologists (0.45 versus 0.63, 0.74 versus 0.71, and 0.80 versus 0.88, respectively). After 6 weeks of clinical experience as second readers, the accuracy of one technologist significantly improved (from 74% to 90%, P = .008), whereas accuracy of the other tended toward improvement (from 74% to 86%%, P = .25). Nonradiologists detected, on average, 6/36 additional polyps (17%) missed by any radiologist, and the sensitivity of 5/7 nonradiologists was significantly greater than at least one of the radiologists (P = .05).
  
  
  CONCLUSIONS
  Nonradiologists can perform similarly to radiologists in interpreting intraluminal findings at CTC, with nonradiologist performance improving even after experience with more than 100 cases. Skilled nonradiologists may play a vital role as a second reader of intraluminal findings or by performing quality control of examinations before patient dismissal.
authors.affiliation: Mayo Clinic School of Medicine, Mayo Clinic Rochester, 200 First Street SW, Rochester, MN 55905, USA.
authors.forename: Kale D
authors.initials: KD
authors.lastname: Bodily
authors.forename: Joel G
authors.initials: JG
authors.lastname: Fletcher
authors.forename: Trudy
authors.initials: T
authors.lastname: Engelby
authors.forename: Mark
authors.initials: M
authors.lastname: Percival
authors.forename: Jared A
authors.initials: JA
authors.lastname: Christensen
authors.forename: Brett
authors.initials: B
authors.lastname: Young
authors.forename: Aaron J
authors.initials: AJ
authors.lastname: Krych
authors.forename: Douglas C
authors.initials: DC
authors.lastname: Vander Kooi
authors.forename: Drew
authors.initials: D
authors.lastname: Rodysill
authors.forename: Jeff L
authors.initials: JL
authors.lastname: Fidler
authors.forename: C Daniel
authors.initials: CD
authors.lastname: Johnson
mesh_terms: D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000000981:diagnostic imaging; D003111:Colonic Polyps / Q000000981:diagnostic imaging; D023881:Colonography, Computed Tomographic / Q000706:statistics & numerical data; D006801:Humans; D015588:Observer Variation; D011871:Radiology / Q000193:education / Q000592:standards; D012680:Sensitivity and Specificity; D013337:Students, Medical; D013679:Technology, Radiologic / Q000592:standards