The Association between Near Work Activities and Myopia in Children-A Systematic Review and Meta-Analysis.
Level 3 - non-randomized controlled study
Systematic review and meta-analysis of observational (cohort and cross-sectional) studies
PubMed 26485393 · doi:10.1371/journal.pone.0140419
What was done
A systematic review and meta-analysis was conducted using MEDLINE, Embase, and the Cochrane Library for articles published between 1989 and 2014. The authors included 12 cohort studies and 15 cross-sectional studies covering 25,025 children aged 6 to 18 years. Study-level data on near work activities and myopia were pooled using random-effects or fixed-effects models (for analyses with fewer than 5 studies), with heterogeneity evaluated using the I2 statistic.
What was found
Increased time spent on near work activities was associated with higher odds of myopia (odds ratio [OR] = 1.14; 95% CI = 1.08–1.20). Each additional diopter-hour per week of near work was associated with a 2% increase in the odds of myopia (OR = 1.02; 95% CI = 1.01–1.03).
Why it matters
This review quantifies the modest positive association between near work activities and myopia in children, supporting near work as an environmental risk factor.
Limits
The synthesis relies entirely on observational studies (cohort and cross-sectional), which limits causal inference. The abstract does not report specific exposure assessment methods (such as objective tracking versus self-report questionnaires), degree of statistical heterogeneity, or control for major confounders like outdoor time and parental myopia.
Cited by
- supports Prolonged close-distance viewing can cause myopia by altering the shape of the eyeball and lens.