Alcohol Marketing, Adolescent Drinking and Publication Bias in Longitudinal Studies: a Critical Survey Using Metaanalysis

This paper presents a meta-analysis of prospective cohort (longitudinal) studies of alcohol marketing and adolescent drinking, which accounts for publication bias. The paper provides a summary of twelve primary studies of the marketing-drinking relationship. Each primary study surveyed a sample of youth to determine baseline drinking status and marketing exposure, and re-surveyed the youth to determine subsequent drinking outcomes. Logistic analyses provide estimates of the odds-ratio for effects of baseline marketing variables on adolescent drinking at follow-up. Using meta-regression analysis, two samples are examined in this paper: 23 effect-size estimates for drinking onset (initiation); and 40 estimates for other drinking behaviors (frequency, amount, bingeing). Marketing variables include ads in mass media, promotion portrayals, brand recognition, and subjective evaluations by survey respondents. Publication bias is assessed using funnel plots that account for “missing” studies, bivariate regressions, and multivariate meta-regressions that account for primary study heterogeneity, heteroskedasticity, data dependencies, publication bias, and truncated samples. The empirical results are consistent with publication bias, omitted variable bias in some studies, and lack of a genuine effect, especially for mass media. The paper also discusses “dissemination bias” in the use of research results by primary investigators and health policy interest groups.