Outdoor Scene Classrooms arrest myopia development: A school-based Randomized Clinical Trial

Reduced time outdoors is an important factor promoting the development of myopia. The spatial frequency spectra of man-made indoor and outdoor environments, which are impoverished in high spatial frequencies (HSF), may be a contributor to human myopia development. This randomized clinical trial aimed to investigate whether HSF enhancing classroom-- outdoor scene classroom (OSC) can arrest myopia development in children. Here we showed the OSC was protective in slowing down myopic shift among children who were not myopic at baseline. The one-year change of spherical equivalent was 0.22D less among baseline hyperopic children, and 0.18D less among baseline emmetropic children in the OSC group compare to traditional classroom group. The protective effect of OSC is comparable to the time spent outdoors (Efficacy: OSC=37.1% vs. Outdoor=19.2%) and the 0.01% atropine (Efficacy: OSC=42.4% vs. 0.01% Atropine=30.9%). The study found that the OSC was protective in myopia prevention, especially in hyperopic children. Large implementation of OSC provides an alternative strategy to increased time outdoors in myopia prevention, and provides an approach that involves less disruption to school routines. Chinese Clinical Trial Registry identifier: ChiCTR2000040704.