Myopia affects 20-30% of young students: increasing time spent outdoors may be a preventive strategy
Myopia is on the rise among Chinese children: in a group of 4741 school children, the incidence of this refractive error was found to be between 20% to 30%. Even though myopia is rising worldwide, this growth has been particularly significant in China.
This study was conducted on a cohort of 19 primary schools (2010-2015) and on another group of 22 junior high schools (2010-2012): all schools were randomly chosen at rates proportional to the number of schools in each of the 11 districts of the city of 
Guangzhou.
The incidence of myopia among Chinese students […] is among the highest of any cultural or ethnic group”. This is what the group of Chinese-Australian university researchers stated in an article published on Jama Ophthalmology. The same researchers suggest the adoption of preventive strategies, such as increasing time spent on outdoor activities, also from childhood.
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