To compare the prevalence of eye disease between children and adolescents with diabetes mellitus and healthy people, and to analyze the related factors of eye diseases in diabetic patients.

A cohort study. From January 2018 to 2028, 300 cases of diabetic children in Children's Hospital of Fudan University in Shanghai will be selected as case group, and 300 healthy children without diabetes will be selected as the control group.

The purpose of the study is to guide and regulate eye health screening of children and adolescents with diabetes in Children's Hospital of Fudan University in Shanghai, build up the ranks with the general practitioner as the backbone combined, and provide comprehensive, continuous, and dynamic information service to diabetic eye disease health management. We expect to reduce the prevalence rate of diabetic eye disease, blindness and visual impairment of DR, and improve diabetics consciousness of eye health maintenance, thus upgrading the level of eye disease prevention and treatment in Shanghai.

Inclusion Criteria:

• (1) provision of a written informed consent by a guardian;
• (2) age over 5 years and less than 18 years;
• (3) diagnosis of type 1 or type 2 diabetes based on the WHO diagnostic criteria for cases.

Exclusion Criteria:

• (1) eyelid diseases - eyelid entropion, eyelid ectropion, eyelid, ptosis, and palpebral dyskinesia;
• (2) conjunctival diseases - pterygium and conjunctivitis;
• (3) history of ocular surface chemical injury or use of eye drops with moisturizing artificial tears;
• (4) history of eye surgery within 6 months or history of retinal laser photocoagulation;
• (5) systemic diseases - Sjogren syndrome, Parkinson's disease, rheumatoid arthritis, Grave 's disease, systemic lupus erythematosus, and others.

From January 2018 to 2028, children who are diagnosed with diabetes at the Children's Hospital of Fudan University in Shanghai, will be recruited as cases of diabetes. We will also recruit children without diabetes, who will be matched for age and gender, from this hospital as controls.