To describe the design, methodology and baseline characteristics of the Shanghai Cohort study of Diabetic Eye disease (SCODE) study, a community-based study to determine the prevalence and impact of diabetic eye disease, especially diabetic retinopathy (DR), in adults with diabetes living in Shanghai.

The Shanghai Cohort study of Diabetic Eye disease (SCODE) was a three-year community-based study to carry out a regular ocular health screening and epidemiological analysis for diabetic eye disease in the approximately 8,000 middle-aged and elderly people with diabetes in Shanghai. Through this study, we hope to understand the prevalence, epidemic trend and the features of risk factors distribution on diabetic eye disease, especially on DR.

Meanwhile, our aims also included estimating the ocular fundus changes and visual impairment associated with different grade of DR. Furthermore, the aim of the present study was to investigate the association between serum and urine biochemical parameters and DR.

Inclusion Criteria:

• Adults with diabetes aged 35 years and above; under archives management; residing in Shanghai.

Exclusion Criteria:

• All the study participants have difficulties of mobility or communication.

All the enrolled participants got a yearly examination of diabetic eye disease for three years. Considering that the prevalence of DR gradually increases with age, the target population included adults with diabetes aged 35 years and above under archives management, residing in Shanghai. And the study participants were expected to be freely mobile, clear-thinking, and capable of cooperating to complete the ophthalmic examinations.

Identified individual participant data for all primary and secondary outcome measures will be made available.

Data will be available with in one year of study completion.

Data access requests will be reviewed by an external Independent Review Panel. Requestors will be required to sign a Data Access Agreement.