Crystal Smit

Chapter 4 66 ABSTRACT The current study examined the effectiveness of a social network intervention to improve children’s healthy drinking behaviors. A three-arm cluster randomized control trial designwas used. In the social network intervention, a subset of children was selected and trained as ‘influence agents’ to promote water consumption–as an alternative to sugar-sweetened beverages–among their peers. In the active control condition, all children were simultaneously exposed to the benefits of water consumption. The control condition received no intervention. Four hundred and fifty-one children ( M age = 10.74, SD age = .97; 50.8% girls) from 11 schools in the Netherlands were randomly assigned to either the social network intervention, active control condition, or control condition. Structural path models showed that children exposed to the social network intervention consumed .20 less sugar- sweetened beverage per day compared to those in the control condition ( β = .25, p = .035). There was a trend showing that children exposed to the social network intervention consumed .17 less sugar-sweetened beverage per day than those in the active control condition ( β = .20, p = .061). No differences were found between conditions for water consumption. However, the moderation effects of descriptive norms ( β = -.12, p = .028) and injunctive norms ( β = .11–.14, both p = .050) indicated that norms are more strongly linked to water consumption in the social network intervention condition compared to the active control and control conditions. These findings suggest that a social network intervention promoting healthy drinking behaviors may prevent children from consuming more sugar-sweetened beverage. Moreover, for water consumption, the prevailing social norms in the context play an important role in mitigating the effectiveness of the social network intervention.