Diabetic retinopathy study.
D000367:Age Factors; D001766:Blindness / Q000517:prevention & control; D003930:Diabetic Retinopathy / Q000628:therapy*; D005500:Follow-Up Studies; D006801:Humans; D007258:Informed Consent; D008028:Light Coagulation; D012107:Research Design; D012109:Research Support as Topic; D013997:Time Factors; D014481:United States; D014792:Visual Acuity