Study on Intervention Effect of Heat-related Health Risk Early Warning Digital Technology for School-age Children

Overview

This cluster randomized trial is conducted in Beijing primary schools to evaluate the efficacy of a WeChat mini-program-based high-temperature early warning intervention on the physical and cognitive health of school-age children. Six participating schools are randomly assigned to two parallel groups. The intervention group receives tiered heat alerts and guided self-health monitoring via the mini-program. The control group follows standard daily school and family routines, with no dedicated digital high-temperature early-warning intervention. The primary outcome is children's executive function after a 2.5-month follow-up. A range of secondary indicators related to physical status, mental health and health behaviors are assessed concurrently to quantify the intervention's benefits in mitigating adverse health outcomes caused by high temperatures.

Detailed description

This pilot study is conducted in Beijing, with 6 primary schools selected as research sites. A stratified cluster randomized controlled design is adopted, with schools as the unit of randomization. Eligible primary schools are randomly assigned to the intervention group and the control group, with 3 schools in each group.

A total of 5 Wisconsin Card Sorting Tests (WCST), 2 health examinations, 2 children's high-temperature protection themed drawing activities, and 5 mini-program questionnaire surveys will be conducted in this study.

The intervention group receives a digital intervention of high-temperature health risk early warning. The research team uses a WeChat mini-program to release corresponding high-temperature health risk level information, health tips, protection science popularization information and other early warning content when the high-temperature health risk level reaches yellow, orange or red, and simultaneously pushes them to head teachers and parents.

The monitoring and survey schedule for the intervention group during the study period is as follows: at baseline and endpoint, unified offline WCST and health examinations will be conducted for children once each, accompanied by one online mini-program questionnaire survey each time. One children's high-temperature protection themed drawing activity will be organized at baseline and at the end of the 3rd month after the intervention, and the works will be uploaded to the mini-program for check-in. At the end of the 1st, 2nd and 3rd months after the intervention, one online follow-up questionnaire and WCST will be completed each month, together with check-in. Meanwhile, blood pressure will be monitored once a week, and daily blood pressure monitoring and check-in will be carried out after each high-temperature health risk early warning release. In addition, after the release of high-temperature health risk early warnings, the intervention group is required to complete check-in for reading and transmitting early warning information, health tips and protection science popularization content, as well as online mini-program surveys on children's awareness of high-temperature health risk early warning information and short-term behavioral patterns. The above WCST and questionnaire surveys will be completed by children with parental assistance; blood pressure monitoring and check-in are the responsibility of head teachers during non-summer vacations and parents during summer vacations.

The control group does not receive the high-temperature health risk early warning intervention and will only complete the corresponding WCST, health examinations, questionnaire surveys and blood pressure monitoring.

Interventions

• Other WeChat Mini-program Based Heat Health Risk Early Warning Intervention
  This study implements a digital early warning intervention targeting children's high-temperature health risks. During the intervention period, when the high-temperature health risk level reaches yellow, orange or red, relevant risk information, health tips and heat protection education materials are released to parents and head teachers via the WeChat mini-program. Parents or teachers pass on the warning information to participating children. During non-summer periods, Beijing's high-temperature

Primary outcome measures

• The primary outcome is the comprehensive total score of children's executive function constructed based on the Wisconsin Card Sorting Test (WCST) [Time frame: at 2.5 months of intervention.]

Secondary outcome measures (12)

• Systolic Blood Pressure [Time frame: at 2.5 months of intervention]
• Diastolic Blood Pressure [Time frame: at 2.5 months of intervention]
• Heart Rate [Time frame: at 2.5 months of intervention]
• Forced Expiratory Volume in 1 second (FEV1) [Time frame: at 2.5 months of intervention]
• Forced Vital Capacity (FVC) [Time frame: at 2.5 months of intervention]
• Peak Expiratory Flow (PEF) [Time frame: at 2.5 months of intervention]
• Forced Expiratory Flow 25-75% (FEF25-75%) [Time frame: at 2.5 months of intervention]
• Fractional Exhaled Nitric Oxide (FeNO50) [Time frame: at 2.5 months of intervention]
• Fractional Exhaled Nitric Oxide (FeNO200) [Time frame: at 2.5 months of intervention]
• Calcium Nitric Oxide (CaNO) [Time frame: at 2.5 months of intervention]
• Fractional Expiratory Carbon Monoxide (FeCO) [Time frame: at 2.5 months of intervention]
• Body Fat Percentage [Time frame: at 2.5 months of intervention]

Eligibility criteria

School inclusion criteria

• Willing to participate in the study.
• Possess adequate facilities and qualified teaching staff.
• The school and teachers maintain good cooperation.
• Class size is no less than 35 students.
• All participating classrooms are equipped with air conditioners.

Participant inclusion criteria

• Fourth-grade primary school students aged 9 to 11, of all genders.
• Voluntary participation by students and their parents, good compliance, and signed informed consent.
• At least one adult family member has an internet-enabled mobile device.
• Good general health with no history of severe physical or mental disorders.
• Local permanent residents with a residency of no less than 6 months.

Participant exclusion criteria

• Participants who are unable or refuse to complete required examinations.
• Students receiving psychological or psychiatric treatment that may confound the study results.
• Those currently enrolled in other interventional clinical studies that may affect outcome assessment.
• Any other conditions deemed ineligible by the research team. Any participant meeting any of the above exclusion criteria will be excluded from the study.

Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.

Healthy volunteers: Yes

Study design

Allocation

Randomized

Model

Parallel assignment

Masking

Double blind

Primary purpose

Prevention

Study locations

Center list to be confirmed — check the primary protocol.

Publications

• Lei J, Sun Q, Chen R, Zhu Y, Zhou L, Xue X, Fang J, Du Y, Wang Y, Li T, Kan H. Respiratory Benefits of Multisetting Air Purification in Children: A Cluster Randomized Crossover Trial. JAMA Pediatr. 2025 Feb 1;179(2):122-128. doi: 10.1001/jamapediatrics.2024.5049. PMID 39621320
• Wang Y, Sun Y, Ban J, Fang J, Sun Q, Du Y, Liu Y, Dong H, Wang Q, Chen C, Zhang Y, Ma R, Chen R, Kan H, Li T. Cognitive benefits of air purification among schoolchildren: A randomized, double-blind, crossover trial. Innovation (Camb). 2026 Feb 5;7(5):101304. doi: 10.1016/j.xinn.2026.101304. eCollection 2026 May 4. PMID 42100097
• Pan CY, Tsai CL, Chu CH, Sung MC, Huang CY, Ma WY. Effects of Physical Exercise Intervention on Motor Skills and Executive Functions in Children With ADHD: A Pilot Study. J Atten Disord. 2019 Feb;23(4):384-397. doi: 10.1177/1087054715569282. Epub 2015 Feb 2. PMID 25646023
• Assari S, Zare H. Extreme Heat Exposure is Associated with Lower Learning, General Cognitive Ability, and Memory among US Children. Open J Neurosci. 2025;3(1):10-22. doi: 10.31586/ojn.2025.1277. Epub 2025 Jan 10. PMID 40027445
• Perera F, Nadeau K. Climate Change, Fossil-Fuel Pollution, and Children's Health. N Engl J Med. 2022 Jun 16;386(24):2303-2314. doi: 10.1056/NEJMra2117706. No abstract available. PMID 35704482
• Romanello M, Napoli CD, Green C, Kennard H, Lampard P, Scamman D, Walawender M, Ali Z, Ameli N, Ayeb-Karlsson S, Beggs PJ, Belesova K, Berrang Ford L, Bowen K, Cai W, Callaghan M, Campbell-Lendrum D, Chambers J, Cross TJ, van Daalen KR, Dalin C, Dasandi N, Dasgupta S, Davies M, Dominguez-Salas P, Dubrow R, Ebi KL, Eckelman M, Ekins P, Freyberg C, Gasparyan O, Gordon-Strachan G, Graham H, Gunther S PMID 37977174
• Ebi KL, Capon A, Berry P, Broderick C, de Dear R, Havenith G, Honda Y, Kovats RS, Ma W, Malik A, Morris NB, Nybo L, Seneviratne SI, Vanos J, Jay O. Hot weather and heat extremes: health risks. Lancet. 2021 Aug 21;398(10301):698-708. doi: 10.1016/S0140-6736(21)01208-3. PMID 34419205
• He M, Xiang F, Zeng Y, Mai J, Chen Q, Zhang J, Smith W, Rose K, Morgan IG. Effect of Time Spent Outdoors at School on the Development of Myopia Among Children in China: A Randomized Clinical Trial. JAMA. 2015 Sep 15;314(11):1142-8. doi: 10.1001/jama.2015.10803. PMID 26372583

Identifiers

NCT: NCT07643571 · NIEH202643

Primary sources (government registries)

• ClinicalTrials.gov (US NIH)

View this study on ClinicalTrials.gov ↗