Discussions in the classroom Investigating the role of interpersonal communication of teachers and students within a school-based health intervention

Many young individuals engage in unhealthy behaviors during late adolescence. To discourage these individuals from engaging in unhealthy behaviors, schools often provide school-based health interventions. However, effects of these interventions are often limited and inconsistent. Outside the school context, interpersonal communication has often been shown to explain the effectiveness of health interventions. Interpersonal communication has not received much attention in the context of school-based health interventions. Therefore, the overall aim of this dissertation was to investigate interpersonal communication in the context of a school-based health intervention that stimulates healthier lifestyles among older adolescents. To this end, a cluster-randomized controlled trial was used to study interpersonal communication and (predictors of) the three health behaviors alcohol use, snacking, and exercising in a newly developed school-based health intervention. Findings of this dissertation offer several new insights. First, conversational frequency and valence are both related to the (predictors of) health behaviors. Second, findings demonstrate that how positive students evaluate a school-based health intervention results in healthier and more frequent discussions about the health behaviors, which in turn, lead to healthier predictors of health behaviors. Third, teaching an intervention with higher levels of clarity results in healthier predictors of health behavior. Fourth, sticking to the intervention protocol somewhat improves the intervention effectiveness. Together, findings of this dissertation demonstrate that interpersonal communication among students and their social environment, as well as, teacher-related interpersonal communication can influence intervention effectiveness.