Supplementary Material for: Polysubstance Use Is Positively Associated with Gaming Disorder Symptom Severity: A Latent Class Analytical Study

Introduction: The link between gaming disorder (GD) and substance use amongst adolescents is not clear. Some studies reported positive associations, whereas others suggested that alcohol and illicit drug use are not related to GD severity. Objectives: The present study aimed to identify empirically based latent classes of alcohol and illicit drug use amongst adolescents and explore their associations with GD symptom severity and whether endorsement of specific criteria of GD is linked to the membership of latent classes of alcohol and illicit drug use. Methods: Data of the national sample of Hungarian adolescents from the Health Behaviour in School-aged Children survey (N = 2,768; females: 52.08%; mean age: 16.73 years) were analysed. Measures for frequency of alcohol and illicit drug use, gaming, GD symptom severity, and life satisfaction were included in the analyses. Results: Latent class analysis discriminated 4 subgroups of alcohol and illicit drug use: polysubstance users, high-risk alcohol users, moderate alcohol users, and infrequent substance users. Polysubstance users presented significantly higher levels of GD symptom severity and higher odds for endorsement of criteria of “giving up other activities” and “negative consequences.” Conclusions: Positive associations were shown between higher GD severity and the polysubstance using class. The roles of criteria of “giving up other activities” and “negative consequences” were highlighted in more severe substance use patterns. However, GD severity and criteria did not differ as a function of the level of alcohol use. These findings may imply common roots of GD and illicit drug use in adolescents.