Eye screenings for two-year-olds won’t necessarily predict vision impairments by the time the children reach 4.5 years of age, a new study suggests.

The study included 477 children born at risk for neonatal hypoglycemia. The children were given a comprehensive vision screening exam at approximately 54 months. A majority of the children, 74.4%, had also received an eye exam at age two, while 25.6% had not undergone early screenings at 24 months.

Researchers found 80 children (16.8%) had reduced vision at 4.5 years of age; however, the prevalence of reduced vision did not differ between children who had previously been screened at two and those who had not (15.5% vs. 20.5%).

Investigators also reported children with reduced vision at 4.5 years of age were more likely to have had visual abnormalities requiring referral during their 24 month screening. Visual acuity and mean spherical equivalent autorefraction measurements were also worse in two-year-old children who were later classified with reduced habitual visual acuity. Still, unaided binocular visual acuity, non-cycloplegic refractive error and stereopsis measured at age two all showed poor sensitivity and specificity for predicting visual outcomes at 4.5 years of age, researchers said.

“Overall, these results suggest that vision screening using age‐appropriate testing techniques at two years of age does not predict visual outcomes at 4.5 years of age. Vision screening conducted at two years appears to have poor sensitivity and specificity for detecting mild-to-moderate visual impairment later in childhood,” researchers said.