Beijing (Peking)---Myopia and Obesity Comorbidity Intervention (BMOCI)

Myopia changes

Refer to the "Guidelines for the Prevention and Control of Myopia in Children and Adolescents" issued by the National Health Commission in 2019 to check the vision of children. Unaided distance visual acuity should be measured from a standard distance (5 m), using a standard chart of Illiterate E with a white background. The reduced VA was defined as the measurement value of less than 5.0 in either eye. Then, myopia was defined when participants had reduced VA and had spherical equivalent (SE) less than -0.50 D using non-cycloplegic and subjective refraction. Mild myopia was defined as the SE less than -0.50 D but greater than or equal to -3.00 D, moderate myopia was defined as less than -3.00 D but greater than or equal to -6.00 D, and severe myopia was defined as less than -6.00 D.

Time frame: Approximate timing: Approximate timing: Measured in the baseline and the twelfth month of intervention

Height changes

The record is in centimeters and accurate to one decimal place.

Time frame: Approximate timing: Approximate timing: Measured in the baseline and the twelfth month of intervention

Weight changes

Use an electronic scale and check its accuracy and sensitivity before use. The accuracy error shall not exceed 0.1%, that is, the error per 100kg shall be less than 0.1kg.

Time frame: Approximate timing: Approximate timing: Measured in the baseline and the twelfth month of intervention

Waist circumference changes

A tape ruler was used to measure horizontally around the midpoint of the line between the anterior superior iliac crest and the lower edge of the 12th rib (the thickest part of the waist was selected for obese patients);

Time frame: Approximate timing: Approximate timing: Measured in the baseline and the twelfth month of intervention

Hip circumference changes

The subject stands naturally, with the arms drooping and moderately spread, the feet together, the legs are evenly weighted, the hips are relaxed, and the eyes are straight ahead. The tester places the tape on the most protruding part of the back of the buttocks, and circles the buttocks horizontally. During the test, the tape measure should be close to the skin, and the soft tissue should not be pressed. The reading should be taken when the subject exhales calmly. To ensure that the position of the tape ruler is correct, you can move the tape ruler up and down, compare the readings at different positions, and record the maximum value.

Time frame: Approximate timing: Approximate timing: Measured in the baseline and the twelfth month of intervention

Body composition changes

The body composition measurement was conducted using the Tanita BC-420 body composition analyzer, which collects data on body fat percentage. The participants stood on the foot electrodes of the analyzer and held the hand electrode firmly while maintaining a stable posture throughout the process. The measurement was completed using the bio-electrical impedance method, which typically took between 40 to 60 seconds to obtain accurate readings of the aforementioned body composition metrics.

Time frame: Approximate timing: Approximate timing: Measured in the baseline and the twelfth month of intervention

Blood pressure changes

The upper arm medical electronic sphygmomanometer is used to measure blood pressure. During the measurement, the cuff of the sphygmomanometer is securely wrapped around the upper arm at the level of the heart, ensuring a proper fit without constriction. The device is then activated to inflate the cuff, applying pressure to the brachial artery until the pulse is no longer detectable. The pressure is gradually released, and the device records the systolic pressure (the maximum pressure in the arteries during the heart's contraction) and the diastolic pressure (the minimum pressure in the arteries during the heart's relaxation).

Time frame: Approximate timing: Approximate timing: Measured in the baseline and the twelfth month of intervention

Blood glucose change

Blood glucose analysis was conducted using a professional method to evaluate the blood sample. First, a skilled nurse performed venipuncture to collect the blood samples from the participants. The collected blood samples were immediately frozen and stored in a -80℃ freezer until all samples were gathered for unified delivery to the laboratory. The blood samples were sent to a specialized testing center for analysis and result feedback.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Total cholesterol change

Total cholesterol analysis was conducted using a professional method to evaluate the blood sample. First, a skilled nurse performed venipuncture to collect the blood samples from the participants. The collected blood samples were immediately frozen and stored in a -80℃ freezer until all samples were gathered for unified delivery to the laboratory. The blood samples were sent to a specialized testing center for analysis and result feedback.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Low-density lipoprotein cholesterol (LDL-C) change

Low-density lipoprotein cholesterol (LDL-C) was conducted using a professional method to evaluate the blood sample. First, a skilled nurse performed venipuncture to collect the blood samples from the participants. The collected blood samples were immediately frozen and stored in a -80℃ freezer until all samples were gathered for unified delivery to the laboratory. The blood samples were sent to a specialized testing center for analysis and result feedback.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

High density lipoprotein cholesterol (HDL-C) change

High density lipoprotein cholesterol (HDL-C) change was conducted using a professional method to evaluate the blood sample. First, a skilled nurse performed venipuncture to collect the blood samples from the participants. The collected blood samples were immediately frozen and stored in a -80℃ freezer until all samples were gathered for unified delivery to the laboratory. The blood samples were sent to a specialized testing center for analysis and result feedback.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Triglycerides change

Triglycerides was conducted using a professional method to evaluate the blood sample. First, a skilled nurse performed venipuncture to collect the blood samples from the participants. The collected blood samples were immediately frozen and stored in a -80℃ freezer until all samples were gathered for unified delivery to the laboratory. The blood samples were sent to a specialized testing center for analysis and result feedback.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Uric acid change

Uric acid was conducted using a professional method to evaluate the blood sample. First, a skilled nurse performed venipuncture to collect the blood samples from the participants. The collected blood samples were immediately frozen and stored in a -80℃ freezer until all samples were gathered for unified delivery to the laboratory. The blood samples were sent to a specialized testing center for analysis and result feedback.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Saliva test

Professional salivary hormone detection methods were employed to analyze the saliva samples from participants. First, participants were instructed to collect saliva samples at a specified time point, typically upon waking in the morning. Collected saliva samples were stored in sterile containers and refrigerated promptly to prevent hormone degradation. Estradiol was measured from the saliva sample. The testing methods utilized high-sensitivity enzyme-linked immunosorbent assays (ELISA) to ensure precise and reliable results.

Time frame: Approximate timing: Approximate timing: Measured in the baseline and the twelfth month of intervention

Urine sample detection changes

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).

Time frame: Approximate timing: Approximate timing: Measured in the baseline and the twelfth month of intervention

Sleep diary

To understand students' sleep duration, data collection was conducted using sleep diaries. Each participant was required to record at least one school day and one weekend day consecutively. The sleep diary primarily recorded bedtime, actual sleep onset time, and morning wake-up time. These data were used to calculate total sleep duration per night.

Time frame: Approximate timing: Measured in the six month of intervention

Night lighting changes

Put the photometer on the bedside table of the bedroom and program it to continuously collect light information every 60 seconds.

Time frame: Approximate timing: Measured in the third month of intervention

Basic information-for student

This is part of student questionnaire, which was filled by students or with the help of their parents. Basic information includes students' school, grade, class, name, gender, and date of birth.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Knowledge mastery-for student

This is part of student questionnaire, which was filled by students or with the help of their parents. The knowledge mastery part assessing health knowledge focus on whether students can distinguish behaviors include key message of '22510ss' that promote health. Responses were categorized as "Correct" "Incorrect" or "Don't Know" The total score is the sum of each item (0 to 7), "Correct" for 1 point, and "Incorrect" "Don't Know" for 0 point. A higher total score indicates a better understanding of health knowledge.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Behavior practice-for student

This is part of student questionnaire, which was filled by students or with the help of their parents. The health behavior section of the questionnaire surveys students on their screen time, consumption of fruits and vegetables, intake of high-quality protein, frequency of consuming sugary drinks, and frequency of vision and weight measurement. We calculate the score of '22510ss' key healthy behavior based on their questionnaire results. Each behavior earns one point for completion, and the total score for the items is calculated. The highest score is 7 points, and the lowest is 0 point. Higher points indicate stronger health action capabilities among students.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Myopia and obesity intervention promotion/barrier factors-for student

This is part of student questionnaire, which was filled by students or with the help of their parents. This section of the questionnaire investigates factors that promote or hinder students' implementation of healthy behaviors, including school support, family influence, and peer influence. A five-point Likert scale ("Strongly Agree" is scored 5 points, and "Strongly Disagree" is scored 1 point) is used, and if more than 75% of respondents choose "Agree" or "Strongly Agree," the factor is considered to have a strong promoting or hindering effect.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Dietary questionnaire-for student

This is part of student questionnaire, which was filled by students or with the help of their parents. We used DQQ-China (Dietary Quality Questionnaire for China) to assess the dietary quality of student. DOQ collects dietary consumption data from 29 food groups and is used to calculate the Global Dietary Recommendation (GDR) score. The GDR score ranges from 0 to 18 and reflects adherence to the global dietary guidelines proposed by the World Health Organization (WHO). Higher GDR scores indicate better adherence to WHO's global dietary recommendations. Dietary quality classification based on the GDR score is as follows: High dietary quality: GDR ≥ 10; Moderate dietary quality: 8 ≤ GDR \< 10; Low dietary quality: GDR \< 8.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Physical activity questionnaire-for student

This is part of student questionnaire, which was filled by students or with the help of their parents. International Physical Activity Questionnaire (IPAQ) was used to assess physical activity levels, which includes the frequency, duration, and intensity of physical activities such as walking, moderate-intensity activities, and vigorous-intensity activities over the past 7 days, and the long form providing a more detailed assessment over a longer period. The total physical activity score was usually calculated in terms of MET-minutes/week (Metabolic Equivalent of Task), Based on the MET values (\<600, 600-1500, \>1500), students' activity levels are classified as low, moderate, or high.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Sleep questionnaire-for student

This is part of student questionnaire, which was filled by students or with the help of their parents. The Center for Epidemiologic Studies Depression Scale (CES-D) was employed, each question on the MEQ-5 is answered on a scale that reflects the degree of preference for morning or evening activity. The scores from the five items are summed up to generate an overall score that reflects the individual's chronotype: The total score of the MEO-5 ranges from 4 to 25. The scoring categories are as follows: 4-7 points: Definitely Evening Type; 8-11 points: Moderately Evening Type; 12-17 points: Intermediate Type; 18-21 points: Moderately Morning Type;22-25 points: Definitely Morning Type.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Mental health questionnaire-for student

This is part of student questionnaire, which was filled by students or with the help of their parents. The Center for Epidemiologic Studies Depression Scale (CES-D) was employed to assess the frequency and severity of depressive symptoms The CES-D consists of 20 items using a 4-point Likert scale (0 = "Rarely or none of the time," 3 = "Most or all of the time"). Scores for each item are summed, with higher total scores indicating more severe depressive symptoms. The total score ranges from 0 to 60. Generally, a score of 16 or higher is considered indicative of clinically significant depressive symptoms.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Basic information -for patents

This is part of parents' questionnaire. Basic information includes their child's school, grade, class, name, gender, and date of birth, as well as their relationship, sibling information, birth information of the child, and the parents' age.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Myopia and obesity status-for patents

This is part of parents' questionnaire. This section surveys the height, weight, vision status, and the presence of diseases such as hypertension and diabetes in the father and mother.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Knowledge mastery-for patents

This is part of parents' questionnaire. The knowledge mastery part assessing health knowledge focus on whether students can distinguish behaviors include key message of '22510ss' that promote health. Responses were categorized as "Correct" "Incorrect" or "Don't Know" The total score is the sum of each item (0 to 7), "Correct" for 1 point, and "Incorrect" "Don't Know" for 0 point. A higher total score indicates a better understanding of health knowledge.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Behavior practice-for patents

This is part of parents' questionnaire. The health behavior section of the questionnaire surveys parents on their screen time, consumption of fruits and vegetables, intake of high-quality protein, frequency of consuming sugary drinks, and frequency of vision and weight measurement. We calculate the score of '22510ss' key healthy behavior based on their questionnaire results. Each behavior earns one point for completion, and the total score for the items is calculated. The highest score is 7 points, and the lowest is 0 point. Higher points indicate stronger health action capabilities among students.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Child sleep quality-for patents

This is part of parents' questionnaire. This section of the questionnaire surveys parents about their child's sleep performance using Sleep Disturbance Scale for Children (SDSC). The SDSC consists of 26 items that cover various aspects of sleep, categorized into different domains, it uses a 5-point Likert scale (1 = "never," 5 = "always"), where parents report how often their child experiences each symptom. The scores are summed to generate a total score and sub-scores for each domain. Total score range of 26 to 130, we used the following thresholds to classify the severity of sleep disturbances: Score \< 38: Considered no significant sleep disturbance; Scores between 38 and 45: Mild sleep disturbance; Score \> 45: Significant sleep disturbance.

Time frame: Approximate timing: Measured in the baseline and the twelfth month of intervention

Basic information -for doctors of school

This is part of school questionnaire. Basic information includes the school doctors' gender, age, education level, and workplace.

Time frame: Approximate timing: Measured in the sixth month of intervention

Promotion/barrier factors in health working --for doctors of school

This is part of school questionnaire. We investigated the promoting and hindering factors in schools' efforts to improve students' health behaviors, including items such as the school's educational philosophy, school environment, and level of school support. The items are scored using a 5-point Likert scale ("Strongly Agree" is scored 5 points, and "Strongly Disagree" is scored 1 point). If more than 50% of school doctors select "Strongly Agree" for a particular item, it is considered an important promoting or hindering factor.

Time frame: Approximate timing: Measured in the sixth month of intervention