Maartje Boer

SMU AND WELLBEING ACROSS COUNTRIES 121 4 countries intense users reported higher levels of friend support than non- intense users, intense SMU may often even reflect social engagement, participation, and inclusion, rather than a risk behavior. In contrast, our findings emphasize the potential harm of problematic SMU, as problematic SMU was negatively associated with all wellbeing domains across all countries. This finding underlines the importance of considering intense SMU and problematic SMU as two different phenomena. The results thereby concur with previous studies showing that, while intense SMU does not necessarily indicate lower wellbeing, problematic SMU seems to be negatively related to multiple domains of wellbeing (Boer, Stevens, et al., 2020; Marino et al., 2018b; Shensa et al., 2017; Van den Eijnden et al., 2018). Hence, risks to wellbeing may arise, not from the time spent on SMU per se, but rather from the distinguishing features of problematic SMU, such as loss of control over SMU and preoccupation with SMU. It therefore seems pivotal to consider problematic SMU as a confounder when investigating the relationship between SMU intensity and wellbeing, as the two SMU concepts are correlated, but have different associations with adolescent wellbeing. Previous reports of negative associations between SMU and wellbeing (Kelly et al., 2018; Primack & Escobar-Viera, 2017) were therefore potentially driven by unobserved problematic SMU. The finding that intense SMU was mainly negatively associated with wellbeing in countries where the prevalence of intense SMUwas low, and that a lowcountry-level prevalence of problematic SMU strengthened the negative association between problematic SMU and social wellbeing, is in line with other cross-national findings on adolescent wellbeing. For example, research suggests that the negative relationship between bullying victimization and life satisfaction is strongest in schools and countries where the prevalence of bullying victimization is low (Arnarsson & Bjarnason, 2018). These findings suggest that normalization theory, which posits that substance use may not necessarily indicate problematic profiles in contexts where it is relatively prevalent (Haskuka et al., 2018; Pennay &Measham, 2016; Sznitman et al., 2015), may be extended to other behaviors. That is, there may be a general pattern where specific adolescent ‘risk’ behaviors are less indicative of problems, such as lower wellbeing, in contexts where many adolescents show these ‘risky’ behaviors.