Purpose: Digital screen time has been cited as a potential modifiable environmental risk factor that can increase myopia risk. However, associations between screen time and myopia have not been consistently reported. Although myopia prevalence increased before the massive use of digital devices in some countries, with the rise being influenced by education, there may be an added recent effect of screen time. The aim of this systematic review is to determine the association between screen time and the risk of developing (1) prevalent or incident myopia, or (2) the risk of myopia progression in children. Published manuscripts were identified in PubMed, ScienceDirect and the Cochrane Library, and citation lists were reviewed.
Recent findings: Fifteen studies were included (nine cross-sectional and six cohort studies) with a total of 49 789 children aged between 3 and 19 years old. Seven studies found an association between screen time and myopia. The results showed mixed evidence with the more recent studies exposing a trend of association between hours spent by children using screens and myopia. Meta-analysis using a random-effects model was performed in five studies (n = 20 889) that reported odds ratio (OR). The I2 statistics was used to assess heterogeneity. A pooled OR of 1.02 (95% CI: 0.96-1.08; p = 0.48) suggests that screen time is not associated with prevalent and incident myopia in this group of five studies.
Summary: The results for screen time and myopia are mixed. Further studies with objective screen time measurements are necessary to assess evidence of an association between screen time and myopia.
Keywords: children; myopia; screen time.
© 2020 The Authors Ophthalmic & Physiological Optics © 2019 The College of Optometrists.