Prevalence of refractive errors and ocular disorders in preschool and schoolchildren of Ibiporä-PR, Brazil (1989 to 1996)

Purpose: To establish the prevalence of refractive errors and ocular disorders in preschool and schoolchildren of Ibiporä, Brazil. Methods: A survey of 6 to 12-year-old children from public and private elementary schools was carried out in Ibiporä between 1989 and 1996. Visual acuity measurements were performed by trained teachers using Snellen's chart. Children with visual acuity