title: The efficacy of automated "disease/no disease" grading for diabetic retinopathy in a systematic screening programme.
abstract: OBJECTIVE
  To assess the efficacy of automated "disease/no disease" grading for diabetic retinopathy within a systematic screening programme.
  
  
  METHODS
  Anonymised images were obtained from consecutive patients attending a regional primary care based diabetic retinopathy screening programme. A training set of 1067 images was used to develop automated grading algorithms. The final software was tested using a separate set of 14 406 images from 6722 patients. The sensitivity and specificity of manual and automated systems operating as "disease/no disease" graders (detecting poor quality images and any diabetic retinopathy) were determined relative to a clinical reference standard.
  
  
  RESULTS
  The reference standard classified 8.2% of the patients as having ungradeable images (technical failures) and 62.5% as having no retinopathy. Detection of technical failures or any retinopathy was achieved by manual grading with 86.5% sensitivity (95% confidence interval 85.1 to 87.8) and 95.3% specificity (94.6 to 95.9) and by automated grading with 90.5% sensitivity (89.3 to 91.6) and 67.4% specificity (66.0 to 68.8). Manual and automated grading detected 99.1% and 97.9%, respectively, of patients with referable or observable retinopathy/maculopathy. Manual and automated grading detected 95.7% and 99.8%, respectively, of technical failures.
  
  
  CONCLUSIONS
  Automated "disease/no disease" grading of diabetic retinopathy could safely reduce the burden of grading in diabetic retinopathy screening programmes.
authors.affiliation: Biomedical Physics and Grampian Retinal Screening Programme, University of Aberdeen, Foresterhill, Aberdeen.
authors.forename: S
authors.initials: S
authors.lastname: Philip
authors.forename: A D
authors.initials: AD
authors.lastname: Fleming
authors.forename: K A
authors.initials: KA
authors.lastname: Goatman
authors.forename: S
authors.initials: S
authors.lastname: Fonseca
authors.forename: P
authors.initials: P
authors.lastname: McNamee
authors.forename: G S
authors.initials: GS
authors.lastname: Scotland
authors.forename: G J
authors.initials: GJ
authors.lastname: Prescott
authors.forename: P F
authors.initials: PF
authors.lastname: Sharp
authors.forename: J A
authors.initials: JA
authors.lastname: Olson
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D003930:Diabetic Retinopathy / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D008403:Mass Screening; D008875:Middle Aged; D015397:Program Evaluation; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index