Objective:

To evaluate the epidemiological distribution of astigmatism in a large-scale pediatric population and investigate the impacts of astigmatism magnitude and axis on uncorrected visual acuity (UCVA).

Key Findings:

• Overall prevalence of astigmatism was 43.6%, predominantly mild and with-the-rule (WTR) subtype (82.9%).
• Prevalence and severity increased with advancing educational stages.
• Males showed higher susceptibility to WTR orientation, while females were more prone to ATR and oblique.
• Astigmatism magnitude significantly impaired UCVA in non-myopic and low-myopic eyes, but effects were masked in moderate-to-high myopia.
• WTR axis was associated with worse UCVA compared to oblique subtypes, but the absolute difference was clinically negligible.

Interpretation:

WTR is the predominant astigmatism subtype in school-aged children, influenced by concurrent myopization. The magnitude of astigmatism significantly affects UCVA, while the axis orientation's impact is clinically insignificant.

Limitations:

• Study conducted in a single district, which may limit generalizability.
• Cross-sectional design does not allow for causal inferences.
• Potential selection bias despite comprehensive enumeration approach.

Conclusion:

Targeted monitoring and correction strategies for astigmatism may benefit from being tailored to specific genders and refractive profiles.