Measuring the visual environment of children and young people at risk of myopia: a scoping review.

Purpose: Myopia (short-sightedness) is an emerging WHO priority eye disease. Rise in prevalence and severity are driven by changes in lifestyle and environment of children and young people (CYP), including less time spent in bright daylight and more time spent on near-vision activities. We aimed to systematically map the literature describing direct, objective measurements of the visual environment of CYP.

Methods: We conducted searches in Ovid Medline 1946, Ovid Embase and The Cochrane Central Register of Controlled Trials in November 2024. We included primary research written in English on environmental/behavioural factors and myopia onset/progression in CYP 3-18 years. Two reviewers independently screened titles/abstracts/full texts.

Results: We included 34 articles: 21 explored the association of indoor and/or outdoor light exposure and myopia and included light measurements, two near-vision activities, four both light and near-work, four time outdoors without illuminance measurements, and three light exposure based on meteorological data. Most measurements were carried out at the level of individual children, rather than the surrounding environment alone.

Conclusion: Despite limitations in measurement techniques, there is evidence that reduced illuminance, less time spent in bright light and increased daily duration/sustained episodes of near-vision activities and reduced working distance are associated with increased myopia prevalence/progression.