Refractive errors such as hyperopia, myopia, and astigmatism are common in childhood. They may interfere with learning when uncorrected, particularly when near blur and increased accommodative demand reduce reading efficiency and sustained attention. We conducted a systematic review of observational and interventional studies evaluating associations between refractive errors and cognitive or academic outcomes in children and adolescents. PubMed, Embase, and Scopus were searched from inception to January 2025, and reference lists of eligible articles were hand-searched. Twenty-five studies were included: 16 cross-sectional or other nonrandomized analytical studies, 4 cohort studies, and 5 randomized studies. The included studies spanned preschool and school-aged populations across diverse geographic settings and assessed outcomes including early literacy, attention, visual-motor integration, reading speed, grades, and standardized academic performance. Across preschool studies, uncorrected hyperopia showed a consistent association with poorer early literacy and attention-related outcomes. In school-based studies, observational evidence generally linked uncorrected refractive error or reduced habitual visual acuity to lower academic attainment. Interventional and randomized evidence suggests that spectacle provision can produce modest improvements in reading efficiency and mathematics performance in some settings, including gains of approximately 0.1 standard deviations in some cluster-randomized trials. However, effects varied across programs and were often sensitive to adherence, timing of outcome assessment, implementation intensity, and outcome measurement. Heterogeneity in exposure definitions, outcome measures, and reporting limited quantitative pooling and supports cautious interpretation. Risk of bias was mainly related to confounding in observational studies, limited masking and adherence in randomized studies, and residual uncertainty across heterogeneous evidence. Overall, the evidence indicates that timely detection and correction of refractive errors may support children’s learning, although certainty is limited by heterogeneity, risk of bias, and inconsistent outcome reporting. Future studies should prioritize standardized educational outcomes, rigorous control of confounding, and sustained strategies to optimize spectacle wear.
Elbasheer et al. (Wed,) studied this question.