title: Computed Tomography Observer Agreement in Staging Malignant Lymphoma.
abstract: OBJECTIVE
  To determine pretreatment computed tomography observer agreement in patients with newly diagnosed lymphoma.
  
  
  METHODS
  Forty-nine computed tomography scans were reviewed by 3 experienced radiologists, with each scan assessed twice by 1 observer. Predefined nodal and extranodal regions were assessed, and Ann Arbor stages were assigned. K-statistics were defined as poor (κ < 0.2), fair (κ > 0.2 to κ ≤ 0.4), moderate (κ > 0.4 to κ ≤ 0.6), substantial (κ > 0.6 to κ ≤ 0.8), and almost perfect (κ > 0.8 to κ ≤ 1).
  
  
  RESULTS
  Nodal interobserver agreement varied from 0.09 for infraclavicular involvement to 0.95 for para-iliac involvement; intraobserver agreement was substantial to almost perfect, except for infraclavicular nodes. Extranodal interobserver agreement varied from 0.56 to 0.88; intraobserver agreement was substantial to almost perfect. Ann Arbor stage interobserver agreement varied from 0.57 to 0.69; intraobserver agreement was substantial.
  
  
  CONCLUSIONS
  Computed tomography observer agreement in staging malignant lymphoma appears to be suboptimal.
authors.affiliation: From the *Department of Radiology and Nuclear Medicine, University Medical Center Utrecht, Utrecht; †Department of Radiology, Medical Center Haaglanden, The Hague; Departments of ‡Radiology and §Nuclear Medicine, Meander Medical Center, Amersfoort; ∥Department of Haematology, VU University Medical Center, Amsterdam; ¶Department of Hematology, Meander Medical Center, Amersfoort; and #Department of Internal Medicine, Bernhove Hospital, Uden; and Departments of **Hematology and ††Radiology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Antoinette
authors.initials: A
authors.lastname: de Jong
authors.forename: Thomas C
authors.initials: TC
authors.lastname: Kwee
authors.forename: Henriëtte M E
authors.initials: HM
authors.lastname: Quarles van Ufford
authors.forename: Frederik J A
authors.initials: FJ
authors.lastname: Beek
authors.forename: Lorentz G B A
authors.initials: LG
authors.lastname: Quekel
authors.forename: John M H
authors.initials: JM
authors.lastname: de Klerk
authors.forename: Josée M
authors.initials: JM
authors.lastname: Zijlstra
authors.forename: Rob
authors.initials: R
authors.lastname: Fijnheer
authors.forename: Inge
authors.initials: I
authors.lastname: Ludwig
authors.forename: Marie José
authors.initials: MJ
authors.lastname: Kersten
authors.forename: Jaap
authors.initials: J
authors.lastname: Stoker
authors.forename: Rutger A J
authors.initials: RA
authors.lastname: Nievelstein
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008198:Lymph Nodes / Q000000981:diagnostic imaging / Q000473:pathology; D008223:Lymphoma / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009367:Neoplasm Staging; D015588:Observer Variation; D011446:Prospective Studies; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed; D055815:Young Adult