Refractive error and preferential looking visual acuity in human infants: a pilot study.

A clinical pilot study comparing refractive error and preferential looking (PL) visual acuity in infants 2 to 12 months of age is described. The PL visual acuity of 30 normal infants without significant visual disorders was assessed using the Acuity Card Procedure. Near retinoscopy was used to determine refractive error. Infants of this sample had monocular PL visual acuities similar to those established by McDonald et al. in a laboratory setting. Statistical analysis of the data for this sample of infants showed that refractive error did not change systematically from 2 to 12 months of age. We have found that results obtained with the Acuity Card Procedure in a clinical setting agree with infant visual acuity as described in the research literature. Refractive error did not correlate with changes in PL visual acuity in infants 2 to 12 months of age.