Related Experiment Video
Updated: Mar 7, 2026
Binocular Dynamic Visual Acuity in Eyeglass-Corrected Myopic Patients
Published on: March 29, 2022
Time Outdoors at Specific Ages During Early Childhood and the Risk of Incident Myopia
Rupal L Shah1, Yu Huang2, Jeremy A Guggenheim1
1School of Optometry and Vision Sciences, Cardiff University, Cardiff, United Kingdom.
Insights
Spending more time outdoors in childhood, particularly between ages 3 and 9, significantly reduces the risk of developing myopia later in life. This finding supports outdoor time as a key public health strategy for myopia prevention.
Area of Science:
- Ophthalmology
- Public Health
- Pediatrics
Background:
- Childhood myopia is a growing public health concern.
- Increased time outdoors is a potential preventative strategy for myopia.
- The specific age windows for this association require further investigation.
Purpose of the Study:
- To determine if specific early childhood ages show a stronger association between time outdoors and incident myopia.
- To investigate the protective effect of outdoor time on myopia development.
Main Methods:
- Longitudinal study of 2833 children from ages 2 to 15 years (Avon Longitudinal Study of Parents and Children).
- Assessed time outdoors and reading longitudinally (ages 2-9).
- Measured myopia incidence using noncycloplegic autorefraction (ages 10-15).
- Utilized Cox proportional hazards regression to analyze associations.
Main Results:
- Greater time outdoors from age 3 onwards was linked to reduced myopia risk.
- Hazard ratio for myopia decreased with increased outdoor time (e.g., 0.90 at age 3, 0.86 at age 9 per SD increase).
- Associations remained significant and independent of parental myopia and reading time.
Conclusions:
- Increased time outdoors between ages 3 and 9 is associated with lower myopia incidence from ages 10 to 15.
- The protective effect of outdoor time on myopia appears to strengthen with age within this range.
- Supports public health initiatives promoting outdoor activities for myopia prevention in children.
Purpose:
Time outdoors during childhood is negatively associated with incident myopia. Consequently, additional time outdoors has been suggested as a public health intervention to reduce the prevalence of myopia. We investigated whether there were specific ages during early childhood when the time outdoors versus incident myopia association was strongest.
Methods:
Children participating in the Avon Longitudinal Study of Parents and Children (ALSPAC) were studied from age 2 to 15 years. Parentally reported time outdoors and time spent reading were assessed longitudinally in early childhood (ages 2, 3, 4, 5, 7, and 9 years). Noncycloplegic autorefraction was carried out longitudinally in later childhood (ages 10, 11, 12, and 15 years). Information was available for 2833 participants. Cox proportional hazards regression was used to test for association between time outdoors and incident myopia.
Results:
From 3 years of age onward, greater time outdoors was associated with a reduced risk of incident myopia. The hazard ratio for myopia changed progressively from 0.90 (95% CI 0.83-0.98, P = 0.012) at age 3 years, to 0.86 (95% CI 0.78-0.93, P = 0.001) at age 9 years, for each additional SD of time spent outdoors per day. These associations were independent of two major risk factors for myopia: time reading and number of myopic parents.
Conclusions:
Additional time spent outdoors across the 3 to 9 years age range was associated with a reduced incidence of myopia between ages 10 and 15 years. There was a trend for the association to increase toward the older end of the 3 to 9 years range.
Related Concept Videos
01:17Accessory Structures of the Eye
01:22Photoreceptors and Visual Pathways