Epidemiological characteristics of myopia among school-age children before, during, and after the COVID-19 pandemic: a cohort study in Shenzhen, China

To evaluate the epidemiological characteristics of myopia among school-aged children before, during, and after the coronavirus disease (COVID-19) pandemic. A total of 848,697 students aged 6-15 years from 786 primary and secondary schools in Shenzhen, China, were randomly selected as research subjects. We conducted annual myopia screenings from 2019 to 2022. 2019 was considered before the COVID-19 pandemic, 2020 as during the pandemic, and 2021 and 2022 as after the pandemic. Demographic characteristics, visual acuity, and spherical equivalent refraction (SE) were collected. During the 4-year follow-up period, the uncorrected visual acuity (UCVA) of the study subjects progressed following a trend of -0.18 ± 0.30D (-0.17 ± 0.29D for boys, -0.21 ± 0.32Dfor girls) (