Does having amblyopia affect school readiness and cognitive performance?

Background: Amblyopia is a neurodevelopmental condition causing reduced vision, for which international programmes of whole population child vision screening exist. There is an ongoing debate about the value of screening due to the lack of evidence about meaningful functional impacts of amblyopia and the extent to which these can be mitigated by treatment. / Objective(s): To determine whether amblyopia is associated with school readiness and early cognitive performance. / Method(s): Data from the prospective Millennium Cohort Study of children born in the United Kingdom in 2000-01 and followed-up to age 7 years (n=13,967). Using parental self-report on eye conditions and treatment coded by clinical reviewers, participants were grouped into no eye conditions, strabismus alone, refractive amblyopia, or strabismic/mixed (refractive plus strabismic) amblyopia. The outcomes were poor school readiness using Bracken School Readiness Assessment 10 points) compared to those without any eye conditions, irrespective of whether the treatment had already started. The age-related cognitive trajectories of children with amblyopia did not differ from those without any eye conditions for Naming Vocabulary (p=0.62) and Pattern Construction (p=0.51). / Conclusions: Amblyopia does not appear to affect cognitive performance and trajectories in early schooling and there is no evidence that this is due to a mediating effect of treatment. Although amblyopia combined with strabismus is associated with poor school readiness, this is not translated to poor cognitive performance. These novel findings may explain the lack of associations between amblyopia and educational outcomes in adult life and suggest that the impact of amblyopia on education may not of itself be a justification for population screening aimed at detecting this disorder