title: Observer agreement in the diagnosis of serrated polyps of the large bowel.
abstract: OBJECTIVE
  To assess observer agreement in the diagnosis of colorectal serrated polyps, in particular, serrated adenomas and admixed polyps (i.e. 'polyps with admixed hyperplastic and adenomatous glands').
  
  
  RESULTS
  Sixty cases of large bowel polyps were assessed by four specialist gastrointestinal histopathologists and allocated into one of five categories: serrated adenoma, hyperplastic polyp, conventional adenoma, admixed polyp, and other polyps with serration. Complete agreement amongst all four assessors was seen with only two-fifths of the cases. The overall kappa value for all the assessors distinguishing between all five categories was 0.49. The kappa values for diagnosing serrated adenoma versus all other polyps, and admixed polyp versus all other polyps were 0.38 and 0.3, respectively.
  
  
  CONCLUSIONS
  Specialist gastrointestinal histopathologists show only moderate concordance when distinguishing between serrated colorectal polyps. There is only fair interobserver agreement in the diagnosis of serrated adenomas and admixed polyps of the large bowel.
authors.affiliation: Department of Clinical Sciences at South Bristol, University of Bristol, Bristol, UK. nacs.wong@bristol.ac.uk
authors.forename: Newton A C S
authors.initials: NA
authors.lastname: Wong
authors.forename: Linda P
authors.initials: LP
authors.lastname: Hunt
authors.forename: Marco R
authors.initials: MR
authors.lastname: Novelli
authors.forename: Neil A
authors.initials: NA
authors.lastname: Shepherd
authors.forename: Bryan F
authors.initials: BF
authors.lastname: Warren
mesh_terms: D000236:Adenoma / Q000175:diagnosis* / Q000473:pathology; D015331:Cohort Studies; D003110:Colonic Neoplasms / Q000175:diagnosis* / Q000473:pathology; D003111:Colonic Polyps / Q000175:diagnosis* / Q000473:pathology; D006801:Humans; D015588:Observer Variation; D015203:Reproducibility of Results; D012189:Retrospective Studies