Abstract
Purpose: :
To extend our study of cognitive abilities of low-income preschool children with uncorrected ametropia and the effects of spectacle correction at 6 weeks, and examine the effects after 6 months.
Methods: :
Participants: 88 preschoolers (mean age=4.6 years; female=58.1%; Latino=87.3%), sequentially recruited from the UCSD Eyemobile, 44 children with previously uncorrected ametropia and 44 group-matched emmetropic controls. Ametropia was determined by cycloplegic retinoscopy as bilateral hyperopia ≥ 4 D in 3 to 5-year olds, astigmatism ≤ -2 D in 3-year olds and ≤ -1.50 D in 4- and 5-year olds, or a combination of both, and emmetropia as ≤2 D and ≥ -1 D in both eyes.Procedure: The ammetropic group was assessed before, 6 weeks, and 6 months after correction, and compared to the emmetropic controls. Compliance was monitored.
Results: :
At 6-week follow-up with 44 subjects per group, the interaction on VMI became highly significant, p < .005. The ametropic group did not improve significantly more on WPPSI-R Performance Scale than the emmetropic controls, p = .35. At 6-month follow-up with 22 subjects per group, an interaction was found on WPPSI-R, p = .007: The ametropic goup improved 10.6 points, p < .001, compared to 2.7 points in the emmetropic group, p = .18, resulting in an observed standardized effect size of 0.86 and a power of 0.79. The ametropic group was 9.15 times more likely to improve by at least 5 points on both measures than emmetropic group.
Conclusions: :
These findings suggest that refractive correction resulted in gradual improvement in visual motor integration related scores, beginning at 6-week follow-up and extending to 6 months.
Keywords: visual development: infancy and childhood • refractive error development • plasticity