Screening for Hyperopic Reserve in Kindergarten

This population-based hyperopic reserve screening targeted all senior kindergarten children across Beijing (This is a population-based census, rather than a sample survey, covering all senior kindergarten children in Beijing.). The project covered all kindergartens in Beijing (more than 2,200 kindergartens in totals in year 2026), with anticipated 134,000 children enrolled (The roster of 134,000 children was verified kindergarten by kindergarten and provided by educational authorities before project initiation. Only children who signed informed consent underwent screening; therefore, the actual screened sample size would be smaller than 134,000.). Initiated by the Beijing Municipal Education Commission (provide the funding), the screening was implemented by Capital Medical University and supported by Beijing Tongren Hospital.

The ophthalmic assessments included visual acuity measurement and comprehensive ocular biometry. Ocular biometric parameters collected were not limited to axial length; corneal curvature and other biometric indicators were also measured. Non-cycloplegic autorefraction was performed to calculate spherical equivalent refraction for evaluating hyperopic reserve status. No anterior segment examination was included in this screening protocol. A standardized parental questionnaire, with 88 questions, was administered to collect information including demographic characteristics, family history of myopia, outdoor activity time, near-work behaviors, screen exposure and sleep duration, to explore factors associated with hyperopic reserve.

Prior to the launch of screening, documents were issued by educational authorities and distributed to all kindergartens. The screening team developed a detailed screening schedule according to the geographic distribution of kindergartens across Beijing, specifying the exact date for completing screening at each kindergarten. All initial screening procedures were conducted on-site at kindergartens. The screening sessions took place between 8:30 a.m. to 11:30 a.m. and between 2:00 p.m. to 4:30 p.m., with kindergartens providing the venue.

Screening was organized by class. Children were brought to designated areas within the kindergarten, usually large activity rooms with a 5-meter space reserved for visual acuity testing. Kindergarten life teachers assisted in maintaining order among children. The testing duration for each class was approximately 20-35 minutes, depending on children's cooperation level.

Unified equipment was used for screening. There were 22 screening teams equipped with 44 sets of self-developed electronic visual acuity charts from Capital Medical University (identical models), 22 NIDEK auto-refractors (identical models), and 22 NIDEK biometers (identical models). Each set of equipment was fitted with a custom crash-resistant transport case, and calibration was performed before measurements.

All collected data were uploaded to the cloud in real time via the project platform without manual entry. In rare cases where data transmission failed due to signal delay, screening records were photographed for archiving and entered manually at a later stage.

A small number of children who had signed informed consent but were absent on the screening day due to illness or other reasons received centralized make-up screening on weekends.

Key principal investigators of this project: Vice President Chen Rui (Chen is the family name) from Capital Medical University, Professor Zhu Huiping (Zhu is the family name) from the School of Public Health, Director Jie Ying (Jie is the family name) of the Department of Ophthalmology at Beijing Tongren Hospital. Other researchers include ophthalmologist Tian Lei (Tian is the family name), ophthalmic researcher Cao Kai (Cao is the family name) from Beijing Institute of Ophthalmology, Beijing Tongren Hospital and Dr. Jiang Jiaxin(Jiang is the family name) from the School of Public Health, Capital Medical University.

The primary aim of this screening was to identify children with insufficient hyperopic reserve at an early stage. Combining ocular biometric data and questionnaire information, the study identified children at high risk of myopia onset, delivered myopia prevention health education to parents and kindergartens, and provided follow-up recommendations for high-risk individuals.

This project represents a milestone in myopia prevention and control in China. Nearly half of the participating children will be referred to Beijing Tongren Hospital and other affiliated hospitals of Capital Medical University that are members of the Hyperopic Reserve Protection Alliance for cycloplegic refraction re-examination. Consequently, the investigators can generate a highly precise profile of visual acuity, refractive status, axial length and other ocular biometric parameters among senior kindergarten children. Using the gold-standard data obtained from cycloplegic refraction, the investigators can refine the measurements acquired under non-cycloplegic conditions. These data will be used to develop predictive models to guide future large-scale screening programmes.