Prevalence, incidence, and risk factors for myopia among urban and rural children in southern China: protocol for a school-based cohort study
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ABSTRACT: Introduction
Myopia is the common cause of reduced uncorrected visual acuity among school-age children. It is more prevalent in urban than in rural areas. Although many myopia studies have focused on the effect of urbanisation, it remains unclear how visual experience in urban regions could affect childhood myopia. This study aims to investigate the incidence and prevalence of myopia among school-age children in urban and rural settings, thereby identifying the environmental factors that affect the onset and progression of myopia. Methods and analysis
A school-based cohort study will be conducted. We will enroll all first-grade students from an urban (10 primary schools) and a rural (10 primary schools) regions of Zhaoqing city, China. Over 3-year follow-up period, students will receive detailed eye examinations annually and complete questionnaires about living habits and environment. In a 5% random subsample of the cohort, physical activity, light intensity and eye-tracking data will be obtained using wearable devices, and high-resolution macular images will be obtained by optical coherence tomography (OCT). The primary outcome is incident myopia, defined as myopia (spherical equivalent refractive of at least −0.5D) detected during follow-up among those without myopia at baseline. Ethics and dissemination
Ethics approval was obtained from the ethics committee of the Zhongshan Ophthalmic Center (number: 2019KYPJ171). Study findings will be published in a peer-reviewed journal. Trial registration number
NCT04219228.
SUBMITTER: Chen X
PROVIDER: S-EPMC8573650 | biostudies-literature |
REPOSITORIES: biostudies-literature
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Project description:ObjectiveThis study aimed to estimate the pooled prevalence of myopia among school-age children in Ethiopia.MethodsEligible articles were searched from PubMed, Embase, and Web of Science databases. In addition, Google Scholar and reference lists of the retrieved articles were searched from 30 July 2022 to 02 January 2023. The preferred reporting of items for systematic reviews and meta-analysis was used to report the search results. Microsoft Excel was used to keep the data. The qualities of eligible studies were checked using the Joanna Briggs Institute critical appraisal checklist for prevalence studies. Analysis was held using STATA Version 11. The degree of heterogeneity was checked using I² statistics. The possible sources of heterogeneity were examined using meta-regression and subgroup analyses. The funnel plot and Egger's test were used to assess the potential publication bias. A correction was made for publication bias using Duval and Twee Die's trim-and-fill analysis. The systematic review registration number is PROSPERO (#CRD42022330541).ResultsWe identified 21 eligible articles including 20,757 subjects. Of those participants, 10,601 (51.1%) and 10,156 (48.9%) were males and females, respectively. A total of 15,152 (73%) participants were urban residents. The estimated prevalence of myopia among school-age children in Ethiopia was found to be 5.26% (95% confidence interval: 4.09-6.42).ConclusionsThe prevalence of myopia among school-age children in Ethiopia is considerable, affecting one in 20 school-age children. Therefore, the authors recommend the stakeholders take extra steps to speed up the implementation of the school vision screening program and its integration plan into the existing school nutrition program.
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