Crystal Smit

Chapter 2 26 ABSTRACT The current pilot study examined the effectiveness of a social network-based intervention using peer influence on self-reported water consumption. A total of 210 children (52% girls; M age = 10.75, SD age = .80) were randomly assigned to either the intervention ( n = 106; 52% girls) or control condition ( n = 104; 52% girls). In the intervention condition, themost influential children in each classroomwere trained to promote water consumption among their peers for eight weeks. The schools in the control condition did not receive any intervention. Water consumption, sugar- sweetened beverage consumption, and intentions to drink more water in the near future were assessed by self-report measures before and immediately after the intervention. A repeated measure MANCOVA showed a significant multivariate interaction effect between condition and time ( V = .07, F (3, 204) = 5.18, p = .002, p η 2 = .07) on the dependent variables. Further examination revealed significant univariate interaction effects between condition and time on water ( p = .021) and sugar-sweetened beverage consumption ( p = .015) as well as water drinking intentions ( p = .049). Posthoc analyses showed that children in the intervention condition reported a significant increase in their water consumption ( p = .018) and a decrease in their sugar-sweetened beverage consumption ( p < .001) over time, compared to the control condition ( p -values > .05). The children who were exposed to the intervention did not report a change in their water drinking intentions over time ( p = .576) whereas the nonexposed children decreased their intentions ( p = .026). These findings show promise for a social network-based intervention using peer influence to positively alter consumption behaviors.