Wang SK, et al. - Among children in primary and junior high schools in China, the incidence of myopia and high myopia based on refraction without cycloplegia was determined in this observational cohort study. Findings suggested that of any cultural or ethnic group the highest incidence of myopia was seen in Chinese students based on refraction without cycloplegia. In Chinese populations, interventions to prevent myopia onset should be started in primary schools, if confirmed with cycloplegic refraction.