Mechanisms of Social Media Effects on Attitudes Toward E-Cigarette Use: Motivations, Mediators, and Moderators in a National Survey of Adolescents.

Because perceived social media realism moderates the effect of exposure to e-cigarette messages on attitude toward e-cigarette use, future intervention efforts should address the realism perceptions. The three-way interaction among exposure, social learning motivation, and social norm indicates the importance of addressing both the online and offline social environments of adolescents. The social media use motivation scale, reflecting perceived affordances, is broadly applicable. Understanding social media use motivations is important, as they indirectly influence attitude toward e-cigarette use via frequency of social media use and/or frequency of exposure to e-cigarette messages on social media.