Purpose The prevalence of myopia in Taiwan has been reported to be increasing in the sequential nationwide survey. The results of our studies demonstrated that the prevalence of myopia, especially high myopia increased among the freshmen in National Taiwan University. These findings may be explained by two possible reasons. First, we found the age of onset of myopia decreased from 12 years in 1983 to 8 years in 2000 in our previous nationwide survey. 1 Second, myopia is influenced