Cao K, et al. - Researchers examined the significance of outdoor time for myopia prevention. Searching databases of Pubmed, Science Direct, the Cochrane Library, the Chinese National Knowledge Infrastructure, and the Wanfang Database, they included five relevant randomized controlled trials with 3,014 participants (age: 6–12 years; follow-up duration: 9–36 months). The analysis supports the value of outdoor time in slowing down the change of axial length and decreasing the risk of myopia.