RESUMO
BACKGROUND: Exposure and introduction to digital media, especially in children, are a current cause for concern. The negative links associated with early screen exposure are extensive. AIMS: To evaluate the association between the time of exposure to a screen in children at 18 months of age and cognitive development in a population-based sample in Southern Brazil. STUDY DESIGN: This was a cross-sectional study corresponding to the fourth wave of a population-based cohort study with pregnant women and later, their children living in the city of Pelotas, Southern Brazil. SUBJECTS: The sample consisted of 470 children who completed the cognitive assessment. OUTCOME MEASURES: Cognitive development was assessed using the Bayley Scales of Infant Development - Third Edition (BSID-III). Exposure to screen time was assessed using a questionnaire completed by the primary caregiver. RESULTS: Of the total, 58.8 % of the children had ≥1 h of screen time per day and the average on the cognitive scale of the entire sample was 96.1 (SD = 14.0). Cognitive development was lower in children whose mothers had lower levels of education (CI 95 % -4.9; -2.1), where boys (CI 95 % 3.2; 8.4) and in children exposed to 2 h or more of screen time/day (CI 95 % -3.6; -0.5). CONCLUSIONS: Exposure to screens may have a significant negative association with children's cognitive development and, therefore, we seek to intervene and to give advice to parents and guardians about the true impact of digital media. Further studies are necessary to consolidate the findings and to disclose information on the topic.