title: CT colonography: accuracy of initial interpretation by radiographers in routine clinical practice.
abstract: OBJECTIVE
  To investigate performance of computed-assisted detection (CAD)-assisted radiographers interpreting computed tomography colonography (CTC) in routine practice.
  
  
  METHODS
  Three hundred and three consecutive symptomatic patients underwent CTC. Examinations were double-read by trained radiographers using primary two-dimensional/three-dimensional (2D/3D) analysis supplemented by "second reader" CAD. Radiographers recorded colonic neoplasia, interpretation times, and patient management strategy code (S0, inadequate; S1, normal; S2, 6-9 mm polyp; S3, > or = 10 mm polyp; S4, cancer; S5, diverticular stricture) for each examination. Strategies were compared to the reference standard using kappa statistic, interpretation times using paired t-test, learning curves using logistic regression and Pearson's correlation coefficient.
  
  
  RESULTS
  Of 303 examinations, 69 (23%) were abnormal. CAD-assisted radiographers detected 17/17 (100%) cancers, 21/28 (72%) polyps > or = 10 mm and 42/60 (70%) 6-9 mm polyps. The overall agreement between radiographers and the reference management strategy was good (kappa 0.72; CI: 0.65, 0.78) with agreement for S1 strategy in 189/211 (90%) exams; S2 in 19/27 (70%); S3 in 12/19 (63%); S4 in 17/17 (100%); S5 in 5/6 (83%). The mean interpretation time was 17 min (SD = 11) compared with 8 min (SD = 3.5) for radiologists. There was no learning curve for recording correct strategies (OR 0.88; p = 0.12) but a significant reduction in interpretation times, mean 14 and 31 min (last/first 50 exams; -0.46; p < 0.001).
  
  
  CONCLUSIONS
  Routine CTC interpretation by radiographers is effective for initial triage of patients with cancer, but independent reporting is currently not recommended.
authors.affiliation: Intestinal Imaging Centre, St Mark's Hospital, Harrow, Middlesex, UK. burlingdavid@yahoo.co.uk
authors.forename: D
authors.initials: D
authors.lastname: Burling
authors.forename: P
authors.initials: P
authors.lastname: Wylie
authors.forename: A
authors.initials: A
authors.lastname: Gupta
authors.forename: R
authors.initials: R
authors.lastname: Illangovan
authors.forename: J
authors.initials: J
authors.lastname: Muckian
authors.forename: R
authors.initials: R
authors.lastname: Ahmad
authors.forename: M
authors.initials: M
authors.lastname: Marshall
authors.forename: S A
authors.initials: SA
authors.lastname: Taylor
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002983:Clinical Competence; D003110:Colonic Neoplasms / Q000000981:diagnostic imaging*; D003111:Colonic Polyps / Q000000981:diagnostic imaging* / Q000473:pathology; D023881:Colonography, Computed Tomographic / Q000379:methods* / Q000592:standards; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D011857:Radiographic Image Interpretation, Computer-Assisted / Q000379:methods; D012015:Reference Standards; D015203:Reproducibility of Results; D013997:Time Factors