Prevention of Myopic Progress by Glasses. Study Design and the First-Year Results of a Randomized Trial among Schoolchildren

Abstract
We report the design and first-year follow-up results of a randomized trial of three different types of corrective lenses: (1) minus lenses with full correction for continuous use (the reference group); (2) minus lenses with full correction for distant vision only; and (3) bifocal lenses. Two hundred and forty 9- to 11-year-old mildly myopic schoolchildren were randomly allocated to the three treatment groups to be followed up to 3 years. During the first year, 73% of the children were compliant with their treatment. Refraction values after the first year were obtained from all but one child. In the second group (spectacles for distant vision only) myopia had progressed somewhat more than in the reference group. In respect of other values (school achievement, reading habits, and accidents) there were no statistically significant differences between the groups.