Prevalence of Refractive Errors in School-Aged Children in the School District of Philadelphia

Abstract

Purpose : To determine the prevalence and severity of refractive errors in school-aged children in grades K-5 enrolled in School District of Philadelphia public schools.

Methods : The Wills Eye Vision Screening Program screened children in grades K-5 on site in public schools between January 2014 and January 2016. The criteria for vision screening failure was 1) an interocular difference of two or more lines in distance visual acuity, 2) distance or near visual acuity worse than 20/40 in either eye in children in grades K-1, or 3) distance or near visual acuity worse than 20/30 in either eye in children in grades 2-5. Children who failed the vision screening received further examination by an on-site optometrist who determined whether the child’s decreased visual acuity could be corrected with eyeglasses. These children were diagnosed with refractive error, a defect in the focusing of light on the retina, which results in blurred vision. The most common refractive errors are myopia, hyperopia, and astigmatism.

Results : Of 14,938 children screened, 1759 (11.8%) exhibited refractive errors: 921 (52.4%) myopia, 488 (27.7%) hyperopia, and 1318 (74.9%) astigmatism. 939 (53.4%) had more than one refractive error diagnosis. In stratifying myopia and hyperopia by severity, mild myopia (-3.00 D < spherical equivalent refraction ≤ -0.50 D) was the most prevalent (present in 43.4% of right eyes and 44.2% of left eyes). The prevalence of myopia increased with age, while the prevalence of hyperopia decreased with age. There was no significant difference in the prevalence of refractive errors on the basis of gender.

Conclusions : Our data show that 11.8% of school-aged children in this urban population exhibited refractive errors that caused suboptimal visual acuity. Therefore, it is critically important to screen school-aged children for vision problems. School-based vision screening programs provide an avenue to identify and correct undiagnosed refractive errors.

This is an abstract that was submitted for the 2017 ARVO Annual Meeting, held in Baltimore, MD, May 7-11, 2017.