Study Supports Preschool-Based Vision Screening Programs to Increase Glasses Wear

Published on: 

Research published in JAMA Ophthalmology supports the continued implementation of preschool-based vision screening programs, as nearly 3 of 4 preschool students consistently wore their glasses at school during the first year of use.

Research published in JAMA Ophthalmology supports the continued implementation of preschool-based vision screening programs, as nearly 3 of 4 preschool students consistently wore their glasses at school during the first year of use. Data also showed students with worse uncorrected baseline visual acuity were more likely to wear glasses compliantly.

“Uncorrected refractive errors account for the majority of visual impairment experienced by children across the world,” the researchers wrote, while “low compliance with early eyeglass wear can limit visual development and ability.”

Negative effects associated with poor vision, including struggles with future literacy, academic success, and quality of everyday life, can be compounded by social inequities faced by children in low-income families.

“Previous studies have shown that disparities in visual impairment are disproportionately observed among urban minority youth, further widening gaps in academic achievement,” the authors explained.


To assess eyeglass wear compliance among preschoolers who received free glasses through an onsite preschool screening program (See Well To Learn [SWTL]), the researchers conducted a longitudinal cross-sectional study of 188 children attending 51 Bay Area Head Start preschools in San Francisco, California.

According to the authors, the findings “suggest that programs involving school-based screening and eyeglass delivery may lessen disparities in accessing pediatric vision care.”

Investigators analyzed compliance by collecting data at regular weekly intervals from preschool teachers. Wear was checked formally upon daily arrival to the classroom and informally throughout the day. Observations were converted to a 5-point compliance score, with a yearly mean calculated for each student. Any score of 4 or greater was considered to be eyeglass wear compliant, meaning the student consistently wore glasses at least every day for more than half of the 8-hour school day. The study took place during the 2017-2018 school year.

All preschool participants were between the ages 3 and 5 and had failed results on vision screening in the fall of 2017. At that time, “fewer than a quarter of parents had suspected that their child’s vision was impaired…further highlighting the importance of early school-based vision testing to detect refractive errors in the first place,” the authors said. Those with diagnosed refractive errors received 2 pairs of glasses and a replacement pair as needed, all at no cost.

Ninety-one of the 188 students were boys (49%), and the mean (SD) student age was 3.89 (0.5) years. Of these, 133 (71%; 95% CI, 64%-77%) had a mean compliance rating of 4 or higher. Additional findings included:

  • The annual mean score of 133 students compliant with eyeglass use was 4.73 (95% CI, 4.67-4.79) vs 2.78 (95% CI, 2.54-3.01) among 55 students noncompliant with eyeglass use.
  • In any given week, between 139 students (74%) and 164 students (87%) were observed to wear their glasses every day, for at least 50% of the time.
  • Baseline uncorrected visual acuity in both the better-seeing and worse-seeing eyes was the only assessed factor that was associated with compliance.
  • In the better-seeing eye, the mean uncorrected visual acuity of students with eyeglass wear compliance was 0.473 logMAR (95% CI, 0.433-0.514 [Snellen equivalent, 20/60]) compared with 0.394 logMAR (95% CI, 0.334-0.454 [Snellen equivalent, 20/50]) for students with noncompliance (P = .03)
  • In the worse-seeing eye, the mean uncorrected visual acuity of students with compliance was 0.576 logMAR (95% CI, 0.530-0.623 [Snellen equivalent, 20/75]) compared with 0.492 logMAR (95% CI, 0.433-0.551 [Snellen equivalent, 20/62]) for students with noncompliance (P = .03)

Overall, visual acuity of the worse-seeing eye and visual acuity of the better-seeing eye “were associated with consistent eyeglass wear compliance at school,” the authors wrote. The finding that poorer visual acuity is associated with higher eyeglass use compliance is consistent with previous studies of adolescents in diverse settings.

Throughout the course of the study, compliance did not fluctuate much for the majority of participants, suggesting that “once a child develops the habit of wearing glasses, further resources may not be required to encourage continued compliance.” SWTL staff also provided continued support to families via 3 follow-up telephone calls in their preferred language to reinforce eyeglass compliance at home and provide strategies to support wear.

The study was limited by missing data, as compliance scores were not recorded every week, and by its relatively short follow-up period of 1 year.

“To increase cost-effectiveness, additional interventions ought to be focused on noncompliance,” the authors wrote.


Sabharwal S, Nakayoshi A. Lees CR, Perez S, de Alba Campomanes AG. Prevalence and factors associated with eyeglass wear compliance among preschoolers from low-income families in San Francisco, California. JAMA Ophthalmol. Published online February 18, 2021. doi:10.1001/jamaophthalmol.2020.7053