Not all norm information is the same: Effects of normative content in the media on young people's perceptions of e-cigarette and tobacco use norms.

Norm information in media can predict individuals' norm perceptions and, ultimately, their behavior. Little research has examined how descriptive norm information manifests in media and impacts beliefs in the real world. Previously, using automated content analysis, we measured and examined longitudinal trends in two types of descriptive norm information, individual use depictions and population norms, pertaining to tobacco and e-cigarette use across six media sources from 2014-2017. Here, we assess how this norm information affected norm perceptions over time by pairing these data with a rolling cross-sectional survey of young people's beliefs and intentions related to these behaviors. We found that individual use depictions predicted some norm perceptions, although the direction of effects varied depending on the source, behavior, and type of perceptions considered. Population norm content did not affect perceptions. These findings highlight that real-world media norm information has real-world effects, and moderators of these effects should be studied.