MAR 18, 2022
The goal of this study was to determine the prevalence of myopia in young Taiwanese children after implementation of an outdoors-based myopia prevention policy and to describe the secular trend of myopia before and during the COVID-19 pandemic.
The study involved repeated population-based, cross-sectional surveys based on the Yilan Myopia Prevention and Vision Improvement Program (YMVIP), which promotes outdoor activities in the Yilan County schools. Included in the analysis were 21,761 kindergarteners from 7 school-year cohorts (years 2014 to 2020). Children were given eye exams at their schools by qualified ophthalmologists and their parents or caregivers were asked to fill out the YMVIP questionnaire regarding medical history and the child’s activities.
After implementation of the YMVIP, the prevalence of myopia continuously decreased for 2 years, from 15.5% to 8.4%. Later cohorts received the full complement of these school-based myopia prevention strategies, and thus the prevalence of myopia remained relatively stable even during the COVID-19 pandemic.
Limitations of the study include its cross-sectional nature, the lack of a randomized control group and any relevant data from prior to 2014 for comparison, difficulties in monitoring compliance with outdoors time, recall bias, and the use of 1% tropicamide rather than 1% cyclopentolate to induce cycloplegia, which may have led to overestimation of myopia prevalence.
This study highlights the considerable impact of strategies to promote outdoor activities in kindergarteners. The authors conclude that, even during the COVID-19 pandemic, the prevalence of myopia can be kept stable with undisrupted school-based preventive strategies.