Related Experiment Video
Updated: Sep 14, 2025

Subjective Refraction Test Using a Smartphone for Vision Screening
Published on: October 18, 2024
Prevalence and patterns of subnormal visual acuity and refractive errors among preschool children in Sucheng
Lei Shen1, Yuqing Cui1, Nana Zhao1
1Nanjing Drum Tower Hospital Group Suqian Hospital, Jiangsu Suqian, 223800, China.
Insights
Preschool children
Area of Science:
- Ophthalmology
- Pediatric Optometry
- Public Health
Background:
- Early detection of visual impairments in children is crucial for development.
- Refractive errors and visual acuity deficits are common in pediatric populations.
- Understanding prevalence and trends informs targeted interventions.
Purpose of the Study:
- To assess visual acuity and refractive status in preschool children in Sucheng District.
- To analyze the incidence and distribution of visual and refractive abnormalities.
- To identify age-related patterns in these conditions.
Main Methods:
- Cross-sectional study of 27,062 children (aged 3-6 years) from 61 kindergartens.
- Utilized standard logarithmic visual acuity charts and Spot VS100 binocular refractive screener.
- Employed chi-square and trend tests for statistical analysis of age-group differences.
Main Results:
- Median visual acuity improved with age (0.63 to 0.80).
- Overall prevalence of subnormal visual acuity was 12.4%, higher in males.
- Refractive abnormalities detected in 13.02% of children, with increasing simple myopia and decreasing hyperopia/astigmatism with age.
Conclusions:
- Older age associated with lower overall refractive abnormality rates but rising simple myopia.
- Findings suggest potential developmental trends, but require longitudinal studies for confirmation.
- Distinguishing developmental trends from cohort effects is essential for accurate interpretation.
Objective:
To investigate the visual acuity and refractive status of preschool children in the Sucheng District of Suqian city and analyze the incidence and distribution patterns of visual and refractive abnormalities in this district METHODS: This cross-sectional study was conducted from April to June 2024 and involved 27,062 children from 61 kindergartens in the district. Standard logarithmic visual acuity charts and the Spot VS100 binocular refractive screener were used to assess visual acuity and noncycloplegic refractive status. Chi-square tests and trend tests were employed to analyze differences in visual acuity and refractive status across age groups.
Results:
Median visual acuity improved from 0.63 (3-year-olds) to 0.80 (6-year-olds). The overall prevalence of subnormal visual acuity was 12.4%, with a significantly higher rate observed in male participants (13.1%) than in female participants (11.5%, P<0.001). The total detection rate of refractive abnormalities was 13.02%. While the proportion of simple myopia tended to increase (χ²=33.15, P<0.001), the proportions of simple hyperopia, mixed astigmatism, and compound myopic astigmatism decreased with age (χ²=11.32, 6.84, 4.57; P<0.05). Although the proportion of emmetropia increased with age (84.41% to 88.15%), this trend was not statistically significant (P=0.121).
Conclusion:
This cross-sectional study suggests an association between older age and lower detection rates of overall refractive abnormalities, alongside rising simple myopia prevalence. However, these findings require longitudinal confirmation to distinguish true developmental trends from cohort effects.
Related Concept Videos
Photoreceptors and Visual Pathways
Focusing of Light in the Eye

