LAUSR

To study the association between television-watching in the earlier years of life and subsequent parents’ concerns about decreased visual acuity in their elementary school-aged child. Population-based longitudinal cohort. Television-watching and its daily duration, as the main exposure, and parents’ concerns for their child’s decreased visual acuity during the school years, as the main outcome, were picked up from yearly questionnaires performed for the Longitudinal Survey of Newborns in the Twenty-First Century involving all babies born in Japan during either of two periods: between January 10 and 17, 2001 or between July 10 and 17, 2001 (N = 47,015). Television-/video-watching as the main form of play of children at the ages of 1.5 years and 2.5 years was significantly associated with parents’ concerns for their child’s decreased visual acuity raised once or more in six surveys conducted between the ages of 7 and 12 years (odds ratio, 1.1 and 1.09; 95% CI 1.05–1.15 and 1.04–1.14, respectively). The association remained significant after adjustment for confounding variables, including child’s sex, preterm birth, multiple birth, mother’s age at delivery, mother’s and father’s education, and residential area. Longer daily duration of television-watching at 2.5 years was significantly associated with concerns for the child’s decreased visual acuity between the ages of 7 and 12 years, but not at the ages of 3.5, 4.5, and 5.5 years. The association remained significant in a sensitivity analysis of 28,820 children who participated in all six surveys. Longer daily exposure to television in children in the earlier years of life was associated with parents’ subsequent concerns about decreased visual acuity in their elementary school-aged child.