U.S. Trends in Adolescent Substance Use and Conduct Problems and Their Relation to Trends in Unstructured In-Person Socializing With Peers.

Purpose: This study examined whether national trends in unstructured in-person socializing with peers (i.e., socializing without goals or supervision) among adolescents could help explain recent declines in adolescent risk behaviors (e.g., substance use, fighting, theft).

Methods: The sample contained of 44,842 U.S. 12th-grade students (aged 17-18 years) from the Monitoring the Future survey (years 1999-2017). Analyses examined (1) prevalence trends, (2) latent factor structure of risk behaviors and unstructured in-person socializing, and (3) whether trends in the unstructured in-person socializing factor accounted for the relationship between time (i.e., survey year) and the risk behavior factor.

Results: Adolescent risk behaviors and unstructured in-person socializing declined by approximately 30% in the U.S., and both formed coherent latent factors. After adjusting for sociodemographics, declines in unstructured in-person socializing accounted for approximately 86% of declines in risk behaviors.

Conclusions: The prevalence of risk behaviors and unstructured in-person socializing behaviors declined among U.S. 12th graders from 1999 to 2017. It is unknown whether such effects are directly causal and/or influenced by unmeasured variables. However, the results provide evidence that national declines in unstructured in-person socializing are a likely component of the explanation for national declines in adolescent risk behaviors.