RESUMO
Free video-sharing platforms such as YouTube are highly popular among young children but may contain low-quality and highly commercialized content. This study aimed to describe the prevalence, duration, and timing of objectively measured mobile YouTube viewing in preschool-aged children and test hypotheses about associations with child individual differences and contextual factors. We analyzed mobile sampling data from 349 English-speaking children aged 3-4.99 years whose parents completed surveys about child, parent, and household characteristics. We assessed whether the child ever viewed YouTube during the sampling week and calculated average daily duration in a subsample of 121 participants with their own mobile devices. We built multivariable logistic regression models to test correlates of mobile YouTube viewership and duration. Children were 3.82 years (SD 0.53), 74.6 percent white non-Hispanic; parents were mostly mothers (93.7 percent), 34.0 (SD 4.6) years, and 37.9 percent had less than a college degree. Mobile YouTube viewing (37.0 percent of children) was more likely in children who used Android devices, shared mobile devices with family members, were older, attended home-based childcare, or had parents with lower educational attainment. Median YouTube duration was 61.2 min/day, with longer durations in children whose parents had lower educational attainment. These results demonstrate that many young children use free video-sharing platforms on mobile devices for long durations, and this practice may be disproportionately higher in children from lower socioeconomic status. Longitudinal research is needed on video-sharing platform viewing and child outcomes.