Xuxi Zhang

photographed was identical at both sites and consisted of the area nasal to the disc and temporal to the macula and the superior and inferior arcades. All photographs were labeled with only the patient’s identification number and were sent for reading in Santa Barbara. Polaroid prints from the Canon camera were examined and graded by an experienced endocrinologist (L.J.) who, before this study, had readings verified by an ophthalmologist until agreement was virtually 100%. An overview grading was assigned for each eye at each examination using the Wisconsin Epidemiologic Study of Diabetic Retinopathy II/III–modified diabetic retinopathy levels, which used a modification of the Airlie House Criteria. Lifestyle intervention study, 2002 Diabetic retinopathy was assessed by indirect and direct ophthalmoscopy by a trained physician (MP) and color fundus photography of two 45° fields on 35 mm film (Elite Chrome 100 ASA, Eastman Kodak, Rochester, N.Y., USA), according to EURODIAB and European Screening Guidelines procedures. Rare microaneurysms and/or microhaemorrhages and/or isolated cotton wool spots at least one disc in diameter away from the fovea defined mild retinopathy. Lesions closer to the macula, and/or more advanced presentations defined more severe retinopathy. Worsening of retinopathy was an increase of at least one level in any eye. VA CSDM, 1996 To determine the incidence and progression of retinopathy in each eye, all of the fundus photographs were graded in a masked fashion using the Early Treatment Diabetic Retinopathy Study (ETDRS) adaptation of the modified Airlie House classification scheme that specifies 13 levels. Meanings of each level are shown in Table 2. Eyes that could not be graded for retinopathy levels because of opacities in the media or enucleation not related to diabetic retinopathy were classified as "cannot grade." In determining retinopathy levels for a participant, the eye with the higher level was given greater weight. For purposes of classification, if retinopathy severity could not be graded in an eye, this eye was considered to have the same score as the participants other eye. Worsening was defined as an increase in the retinopathy severity level of two or more steps. DR, diabetic retinopathy 7 193 Prevention and control of diabetic retinopathy