title: Agreement between clinician and reading center gradings of diabetic retinopathy severity level at baseline in a phase 2 study of intravitreal bevacizumab for diabetic macular edema.
abstract: OBJECTIVE
  To evaluate agreement in diabetic retinopathy severity classification by retina specialists performing ophthalmoscopy versus reading center (RC) grading of seven-field stereoscopic fundus photographs in a phase 2 clinical trial of intravitreal bevacizumab for center-involved diabetic macular edema.
  
  
  METHODS
  Clinicians' grading scale used four levels: microaneurysms only, mild/moderate nonproliferative diabetic retinopathy (NPDR), severe NPDR, and proliferative diabetic retinopathy (PDR) or prior panretinal photocoagulation (PRP) or both. The RC scale used eight levels: microaneurysms only, mild NPDR, moderate NPDR, moderately severe NPDR, severe NPDR, mild PDR, moderate PDR, and high-risk PDR. Percent agreement and kappa statistic were defined by collapsing RC categories to match those used by clinicians.
  
  
  RESULTS
  There was agreement in 89/118 eyes (75%) with kappa = 0.55 (95% confidence interval [0.41, 0.68]). In six eyes, disagreements were of potential substantial clinical importance: five eyes with subtle retinal neovascularization and one with a small preretinal hemorrhage identified only in photographs.
  
  
  CONCLUSIONS
  Clinician grading of retinopathy severity had moderate agreement with RC grading and might be useful for placing eyes into broad baseline categories.
authors.affiliation: Pennsylvania State University College of Medicine, Hershey, PA, USA.
authors.forename: Ingrid U
authors.initials: IU
authors.lastname: Scott
authors.forename: Neil M
authors.initials: NM
authors.lastname: Bressler
authors.forename: Susan B
authors.initials: SB
authors.lastname: Bressler
authors.forename: David J
authors.initials: DJ
authors.lastname: Browning
authors.forename: Clement K
authors.initials: CK
authors.lastname: Chan
authors.forename: Ronald P
authors.initials: RP
authors.lastname: Danis
authors.forename: Matthew D
authors.initials: MD
authors.lastname: Davis
authors.forename: Craig
authors.initials: C
authors.lastname: Kollman
authors.forename: Haijing
authors.initials: H
authors.lastname: Qin
mesh_terms: D020533:Angiogenesis Inhibitors / Q000008:administration & dosage*; D000911:Antibodies, Monoclonal / Q000008:administration & dosage*; D061067:Antibodies, Monoclonal, Humanized; D000068258:Bevacizumab; D003930:Diabetic Retinopathy / Q000145:classification* / Q000188:drug therapy; D006801:Humans; D007267:Injections; D008269:Macular Edema / Q000145:classification* / Q000188:drug therapy; D009887:Ophthalmoscopy / Q000379:methods*; D010781:Photography / Q000379:methods*; D015203:Reproducibility of Results; D042461:Vascular Endothelial Growth Factor A; D014822:Vitreous Body
chemical_list: D020533:Angiogenesis Inhibitors; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab