Abstract
INTRODUCTION: In a previous cross-sectional study of early adolescents, we developed a marketing receptivity index (MRI) that integrates point-of-sale (PoS) marketing exposures, brand recall, and ownership of branded merchandise. The MRI had independent, positive associations with smoking susceptibility among never smokers and with current smoking behavior. The current longitudinal study assessed the MRI's predictive validity among adolescents who have never smoked cigarettes METHODS: Data come from a longitudinal, school-based survey of 33 secondary schools in Argentina. Students who had never smoked at baseline were followed up approximately 17months later (n=1700). Questions assessed: PoS marketing exposure by querying frequency of going to stores where tobacco is commonly sold; cued recall of brand names for 3 cigarette packages from dominant brands but with the brand name removed; and ownership of branded merchandise. A four-level MRI was derived: 1.low PoS marketing exposure only; 2. high PoS exposure or recall of 1 brand; 3. recall of 2 or more brands; and 4. ownership of branded merchandise. Logistic regression models regressed smoking initiation by follow up survey on the MRI, each of its components, and students' willingness to try a brand, adjusting for sociodemographics, social network smoking, and sensation seeking. RESULTS: The MRI had an independent positive association with smoking initiation. When analyzed separately, each MRI component was associated with outcomes except branded merchandise ownership. CONCLUSIONS: The MRI and its components were associated with smoking initiation, except for branded merchandise ownership, which may better predict smoking progression than initiation. The MRI appears valid and useful for future studies.