Crystal Smit

Evaluation of the Motivation Process 5 97 agents in social network interventions to diffuse the target behavior in their social network. The evaluation followed the theoretical framework that guided the design of the Share H 2 O training in order to motivate the selected influence agents and, indirectly, their peers. The Share H 2 O training was grounded in self-determination theory, a prominent theory of human motivation (Deci & Ryan, 1985; Ryan & Deci, 2017). Research on self-determination theory has amply demonstrated that intrinsic motivation, the most autonomous kind of motivation, plays a central role in facilitating health behavioral change and its maintenance (Ng et al., 2012). Intrinsic motivation refers to doing something because it is inherently interesting or enjoyable (Ryan & Deci, 2000, 2017). Individuals who are intrinsically motivated are more likely to adopt and maintain health-related behaviors (Hagger et al., 2014), such as drinking more water (Smit et al., 2018). According to self-determination theory, being intrinsically motivated depends on the satisfaction of three basic psychological needs: autonomy (feeling that one is responsible and has choice), competence (feeling that one is capable and effective), and relatedness (feeling respected and close to others; Deci & Ryan, 2000; Ryan & Deci, 2017). These three needs can be satisfied by creating an autonomy-supportive climate, involving self-determination theory- based techniques, such as providing meaningful rationales, choice, and support, and encouraging self-initiative (Deci & Ryan, 2000; Vansteenkiste et al., 2004). Therefore, in order to optimally motivate the influence agents and, indirectly, their peers, the Share H 2 O training was developed to foster an autonomy-supportive climate. This was done by facilitating their basic psychological needs by applying self-determination theory-based techniques in the training. Research Aims of the Current Study The focus of this study is to evaluate the implementation of the Share H 2 O intervention, in particular whether and how applying self-determination theory- based techniques can motivate the influence agents and, indirectly, their peers. We used reports of both the influence agents and the peers in the classroom networks of the influence agents. Based on the framework guiding the Share