A Large-Scale Test of the Goldilocks Hypothesis

Although the time adolescents spend with digital technologies has sparked widespread concerns that their use might be negatively associated with mental well-being, these potential deleterious influences have not been rigorously studied. Using a preregistered plan for analyzing data collected from a representative sample of English adolescents ( n = 120,115), we obtained evidence that the links between digital-screen time and mental well-being are described by quadratic functions. Further, our results showed that these links vary as a function of when digital technologies are used (i.e., weekday vs. weekend), suggesting that a full understanding of the impact of these recreational activities will require examining their functionality among other daily pursuits. Overall, the evidence indicated that moderate use of digital technology is not intrinsically harmful and may be advantageous in a connected world. The findings inform recommendations for limiting adolescents’ technology use and provide a template for conducting rigorous investigations into the relations between digital technology and children’s and adolescents’ health.

"In this study, we found that the relationships between digital- screen time and mental well-being are nonlinear and that moderate engagement in digital activities is not harmful. The consistently observed concave-down quadratic relations and empirically derived inflection points provide evidence supporting our Goldilocks hypothesis, indicating that post hoc screen-time groupings featured in past research oversimplify the nature of the relations between digital-screen time and adolescents’ well-being. We quantified moderate screen engagement and found that the categories of digital activity we examined are unlikely to present a material risk to mental well-being at these moderate levels, although high levels of engagement may have a measurable, albeit small, negative influence... The relation between screen time and well-being depended, in part, on whether the activities occurred on weekdays or weekends. The adolescents could engage in digital activities between 22 min and 2 hr 13 min longer on weekend days than on weekdays before we found evidence of negative effects. Second, we found evidence that not all digital activities are “created equal.” Those that were pervasive (i.e., using smartphones) or required effortful task switching (i.e., playing video games) had noticeably lower inflection points on weekdays compared with other digital activities. It is possible that some tech activities do interfere with other structured activities during weekdays. For example, it is likely that adolescents are less likely to engage in academic pursuits if they are overusing certain forms of media on weekdays (Junco, 2012), and it may also be the case that these adolescents are less engaged in structured after-school activities that support intrapersonal and social development, and as a result promote well-being (Fletcher, Nickerson, & Wright, 2003). Despite these possibilities, our statistical models suggested that the possible harmful influence of screen time on young people is fairly small, even if one assumes that our correlational data indicate direct causal relations." (Przybylski and Weinstein, 2017: 210-12).