This study tests the proposition that peer influence mediates the effect of sensation seeking, a personality trait, on alcohol use among college students. Cross-sectional data to test this proposition were collected from a representative sample of college students at a large public northeastern university (N = 427). Results of hierarchical regression analyses showed that, as hypothesized, sensation seeking influenced personal alcohol use both directly and indirectly, through its impact on students' frequency of association with alcohol-using peers and the size of their drinking norm misperception. The findings suggest that interventions that seek to limit the frequency in which high sensation seekers associate with peers whose alcohol use is extreme, or alternatively, seek to facilitate social interactions of high sensation seekers with normative peers, may supplement efforts to influence sensation seekers' alcohol and other drug use through tailored mass media advertisements.

Many colleges in the United States are employing social norms marketing campaigns with the goal of reducing college students' alcohol use by correcting misperceptions about their peers' alcohol use. While the typical message used in these campaigns describes the quantity and frequency of alcohol use by the average student on campus, many students may find such a vague comparison other to be socially irrelevant. The current study compares the relative weight of perceptions about alcohol use by distant vs. proximate peers in the prediction of college students' personal drinking behavior. The results of analyzing data collected from a sample of college students at a large public northeastern university (N = 276) show that, as hypothesized, perceived alcohol use by proximate peers (best friends and friends) was a stronger predictor of students' personal alcohol use than perceived alcohol use by more distant peers (such as students in general), controlling for other strong predictors of alcohol use by college students (age, gender, race, off-campus residency, and sensation seeking tendencies). The implications of these findings for the design of more effective social norms messages are discussed.

Many evaluations of public health education campaigns attempt to draw conclusions regarding the effect of messages on audiences' attitudes, beliefs, and behaviors based on observational data. To make causal inferences in these instances, it is necessary to adjust estimated campaign effects for possible selection bias due to systematic differences between respondents exposed to the campaign and those that were not. In particular, it is necessary to adjust for the impact of confounding variables that are likely to be determinants of both campaign exposure and outcomes. In comparison to other available methods for adjusting for selection bias such as multiple regression and instrumental variable methods, propensity scores offer a particularly simple way of adjusting estimates of campaign exposure effects for selection bias. This paper discusses the logic of this approach and illustrates its application to the evaluation of the National Youth Anti-Drug Media Campaign.

In this study, I examined direct and indirect influences of sensation seeking, a personality trait, on adolescent drug use. I hypothesized that some or even most of the contribution of sensation seeking to drug use by adolescents is mediated through association with deviant peers and communication with peers that is favorable toward drug use. I examined the role of additional risk or protective factors in facilitating or impeding association with deviant peers, pro-drug communication, and marijuana use as well. The results of analyzing nationally representative cross-sectional data from the evaluation of the National Youth Anti-Drug Media Campaign support the study's hypotheses and suggest that different factors may protect high sensation-seeking adolescents from using drugs or engaging in activities (e.g., association with deviant peers) that may increase their risk for drug use. I discuss the theoretical, methodological, and practical implications of these findings to the design of health communication interventions.

We present a general theory about how campaigns can have effects and suggest that the evaluation of communication campaigns must be driven by a theory of effects. The National Youth Anti-Drug Media Campaign illustrates both the theory of campaign effects and implications that theory has for the evaluation design. Often models of effect assume that individual exposure affects cognitions that continue to affect behavior over a short term. Contrarily, effects may operate through social or institutional paths as well as through individual learning, require substantial levels of exposure achieved through multiple channels over time, take time to accumulate detectable change, and affect some members of the audience but not others. Responsive evaluations will choose appropriate units of analysis and comparison groups, data collection schedules sensitive to lagged effects, samples able to detect subgroup effects, and analytic strategies consistent with the theory of effects that guides the campaign

The purpose of this study is to examine the relative importance of media coverage and physician advice on the decision of women 40 years and older to obtain a mammogram. Five theoretical models, by which media coverage and physician advice may interact to affect individual health behavior, are presented. These models are tested with time-series regression analysis based on national-level data on mammography utilization and physician advice from the Behavioral Risk Factor Surveillance System (BRFSS) and content analysis of mammography-related national news coverage. Results suggest that although physician advice plays a key role in women's decisions to have mammograms, media coverage of mammography screening also contributes to mammography utilization by women. In particular, media coverage seems to be important for women who do not have regular contact with a physician or access to physicians. A possible conclusion is that mass media and physician advice complement one another in persuading individuals to adopt preventive health behavior.