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.
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.
Scott
Ingrid U
IU
Pennsylvania State University College of Medicine, Hershey, PA, USA.
Bressler
Neil M
NM
Bressler
Susan B
SB
Browning
David J
DJ
Chan
Clement K
CK
Danis
Ronald P
RP
Davis
Matthew D
MD
Kollman
Craig
C
Qin
Haijing
H
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
D020533:Angiogenesis Inhibitors; D000911:Antibodies, Monoclonal; D061067:Antibodies, Monoclonal, Humanized; D042461:Vascular Endothelial Growth Factor A; D000068258:Bevacizumab