Per the results of this systematic review and meta-analysis, daily screen time has a small but significant within-person correlation with later sleep onset; however, short-term daily fluctuations in screen time appear to have minimal impact on sleep duration, efficiency, or quality. Screen time may delay bedtime but is not inherently detrimental to other aspects of sleep health in youth, contrasting with between-person studies showing stronger adverse associations.
Bourke et al. (Mon,) studied this question.