title: Interrater reliability and accuracy in identifying ischemic strokes using computed tomography scans in people with dementia.
abstract: OBJECTIVE
  To assess the reliability and interobserver agreement of stroke identification on neuroimaging in patients presenting with dementia.
  
  
  METHODS
  Comparison study between neurologists, radiology reports, and autopsy.
  
  
  METHODS
  Dementia registry within a health maintenance organization.
  
  
  METHODS
  Dementia patients with computed tomography (CT) scans obtained near the time of diagnosis and postmortem neuropathological examinations (N=99).
  
  
  METHODS
  Three neurologists independently read CT scans for the presence and locations of strokes. Radiology reports from these scans were reviewed. The results from neurologists, radiologists, and autopsies were compared.
  
  
  RESULTS
  The positive predictive value for CT-observed strokes compared with their presence on autopsy was 0.44 to 0.49, regardless of the specialty of the observer. Strokes were present at autopsy in 46 of 99 cases. Agreement between neurologists on the presence of strokes was fair to moderate (kappa=0.27-0.56). Less agreement was found between neurologists and radiologists (kappa=0.00-0.11). Results improved slightly when each case was evaluated as any stroke present versus no stroke on imaging (kappa=0.34-0.75) or for the presence of multiple strokes (kappa=0.17-0.69).
  
  
  CONCLUSIONS
  There is only fair to moderate agreement between observers regarding the identification of strokes on CT scans in patients presenting with dementia. Furthermore, strokes identified on imaging were present on pathology only half the time.
authors.affiliation: Department of Neurology, University of Washington, Seattle, Washington 98195, USA. jbowen@u.washington.edu
authors.forename: James D
authors.initials: JD
authors.lastname: Bowen
authors.forename: Richard
authors.initials: R
authors.lastname: Kamin
authors.forename: James B
authors.initials: JB
authors.lastname: Leverenz
authors.forename: Mark A
authors.initials: MA
authors.lastname: Fishel
authors.forename: Wayne C
authors.initials: WC
authors.lastname: McCormick
authors.forename: Walter A
authors.initials: WA
authors.lastname: Kukull
authors.forename: Eric B
authors.initials: EB
authors.lastname: Larson
mesh_terms: D000368:Aged; D000544:Alzheimer Disease / Q000000981:diagnostic imaging* / Q000469:parasitology; D001344:Autopsy / Q000706:statistics & numerical data; D002544:Cerebral Infarction / Q000000981:diagnostic imaging* / Q000469:parasitology; D015161:Dementia, Multi-Infarct / Q000000981:diagnostic imaging* / Q000469:parasitology; D003937:Diagnosis, Differential; D005260:Female; D006279:Health Maintenance Organizations; D006801:Humans; D008297:Male; D008875:Middle Aged; D015588:Observer Variation; D010348:Patient Care Team / Q000706:statistics & numerical data; D012042:Registries; D015203:Reproducibility of Results; D013223:Statistics as Topic; D014057:Tomography, X-Ray Computed / Q000706:statistics & numerical data*; D014861:Washington