To the Editor.
—A retrospective study in 1980 by Hoyt1 concerning the relationship between early visual experience and subsequent visual disorders compared fifty 5-year-old children whose eyes had been patched during treatment for neonatal jaundice with fifty 5-year-old children from the same intensive-care nursery whose eyes had not been patched. He reported no difference in the incidence of visual disorders between the two groups. However, a somewhat different analysis of his published data suggests otherwise.Low birth weight has been associated with an increase in visual disorders.2 In Hoyt's study, the birth weights of all the children, except two, were below 2,500 g, but the birth weights were dissimilar for the two groups (patched, X̄ = 2,030 g; nonpatched, X̄ = 1,840 g). It was possible that this bias toward heavier infants in the patched group might have confounded the effect of binocular occlusion. Therefore, I excluded the one nonpatched
Glass P. Another Look at Long-term Visual Effects of Binocular Occlusion in Neonates. Arch Ophthalmol. 1984;102(7):968-970. doi:10.1001/archopht.1984.01040030776010