Sheri Madigan
Introduction: Children enter school with varying literacy skills, and these differences tend to get larger over time without intervention.1,2 The home environment, including parent-child shared print book reading and language exposure, has been shown to have a large impact on children’s later academic achievment.3 In addition, shared book reading promotes important parentchild engagement during sensitive periods of development.4 As a result, there have been long-standing efforts to identify factors that may influence the home literacy environment.5–7 With the increased use and accessibility of media devices,8 screen use is becoming a consistent part of children’s day-to-day lives. According to the displacement hypothesis,9 when children are watching screens, they are less likely to spend time practicing skills important for learning and development.10 As such, screen use may be influencing the home learning environment, specifically engagement in off-line enrichment activities such as reading print books,11 and displacement may be one mechanism to explain the relation between screen time and delays in developmental skill acquisition. Although it is possible that screen use interrupts enriching off-line activities such as print book reading,9,12 it is also possible that early reading activities may offset later screen use. However, to test this hypothesis, longitudinal data with repeated measurement are needed to examine directional associations between screen use and reading.