Shanghai Time Outside to Reduce Myopia trial: design and baseline data

Area of Science:

• Ophthalmology
• Public Health
• Pediatrics

Background:

• Myopia is a significant global public health issue.
• Increased time spent outdoors is recognized as a protective factor against myopia development.

Purpose of the Study:

• To detail the methodology and baseline data of the Shanghai Time Outside to Reduce Myopia (STORM) trial.
• To evaluate the effect of increased daily outdoor time on myopia incidence and progression in school children.

Main Methods:

• A 2-year, school-based, prospective, cluster randomized trial involving 6295 children aged 6-9 years in Shanghai.
• Children were randomized into control, 40-min/day, or 80-min/day outdoor time groups.
• Myopia was assessed via cycloplegic autorefraction and axial length measurements; outdoor time was monitored using questionnaires and wearable devices.

Main Results:

• Baseline myopia prevalence was 8.9% in the control group and around 7.7-7.8% in the intervention groups.
• Average time outdoors at baseline was approximately 59 minutes per day across all groups.
• No significant differences in spherical equivalent, myopia prevalence, or time outdoors were observed at baseline between the groups.

Conclusions:

• Myopia prevalence is notably high in 7-year-old Shanghai schoolchildren.
• The STORM trial aims to determine if increasing outdoor time can mitigate myopia onset and progression.
• Further analysis of the trial data is required to establish the efficacy of outdoor time interventions.