Baseline (March-April 2023), first follow-up (July-August 2023), and second follow-up (November-December 2023). The collection of data from study participants at baseline and third follow-up included questionnaire collection, anthropometric indicators, body composition measurements, vision measurements, blood pressure measurements, urine, saliva, and venous blood draws, as well as home questionnaires, school questionnaires, and interventionist physician questionnaires from the community hospitals and the project hospitals; and the first follow-up (the collection of data varied in each district, and was done according to the level of district cooperation) included questionnaire collection, anthropometric measurements, vision measurements, and blood pressure measurements, as well as home questionnaires, school questionnaires, and interventionist physician questionnaires from the community hospitals and the project hospitals.
Myopia and activity records: including nighttime lighting, wake-sleep cycles, and movement. As well as family questionnaires, school questionnaires, community hospitals and project hospital intervention doctor questionnaires. All inspection items are operated by trained and qualified doctors and professional health technicians. The inspection will be arranged in the school, and the whole process is the same as the regular physical examination in the school.
The child required 2 venous blood collections, urine and saliva collections during the year (at the initial stage and at the 3rd follow-up, respectively).
Blood sample testing: 10ml of venous blood is drawn each time for blood routine and blood biochemistry. The blood process is safe. Blood samples include: blood biochemical indicators (fasting blood glucose (FBG), insulin, total cholesterol (TC), triglyceride (TG), low density lipoprotein cholesterol (LDL-C), high density lipoprotein cholesterol (HDL-C) ) and so on).
Hormone testing: Collect saliva samples in the morning and purchase ELISA kits to measure levels of thyroid hormones, estradiol and testosterone.
Urine sample testing: use polypropylene urine cups and urine collection tubes (without PAEs plasticizers) to collect 10 mL of urine from the research subjects, and reserve the sample to collect the first excretion after getting up in the morning, before breakfast and before exercising. The collected urine samples were uniformly stored in a 5mL centrifuge tube and stored in a -20°C refrigerator. Urine PAEs and their metabolites: Ultra-high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) was used to detect seven PAEs metabolites in students' urine: monomethyl phthalate (MMP), phthalic acid Monoethyl ester (MEP), mono-n-butyl phthalate (MBP), mono(2-ethylhexyl) phthalate (MEHP), mono(2-ethyl-5-phthalate) Hydroxyhexyl) ester (MEHHP), mono(2-ethyl-5-oxohexyl) phthalate (MEOHP).
The content of the family and student questionnaires will include general conditions of children, general conditions of parents and families, as well as daily diet, physical activity and sleep. The name of the child will only be used for tracking and will be deleted after one year of observation to ensure that the information of the child and participants will not be leaked. All members of the project team have signed a confidentiality agreement, and all information in the questionnaire will not be leaked to the outside world.
