The effectiveness of a campaign in which children stimulate each other to drink water.

January 2015
March 2015

A health intervention targeting children’s water consumption within schools will be used in a cluster-randomized controlled trial with three conditions: (1) health intervention in which influence agents are selected by peer nominations, (2) health intervention in which agents are randomly selected, and (3) control condition in which no intervention is applied.

In the peer nominations experimental condition children receive a peer nomination questionnaire at baseline in which they are asked to nominate classmates who they “want to be like”, “look up to”, “respect”, “go to for advice”, and regard as “good leaders”. Subsequently, 15% of boys and 15% of girls who receive the most nominations are invited to be trained as influence agents. In the random experimental condition a statistical program is used to randomly select 15% of boys and 15% of girls who are trained to encourage their classmates to drink more water.

The training will be delivered by two experimenters in one 90-minute session. In the first part of the training the health and environmental benefits of water are emphasized. Based on self-persuasion, children generate their own arguments for consuming more water which motivates them to internalize this behavior. In the second part of the training the role of influence agent is explained and children are asked whether they are willing to take on this role. Based on self-determination theory, children may choose in which manner they want to encourage their peers to drink more water. The influence agents receive a reusable water bottle which they could use to stimulate water consumption among their classmates.

The influence agents are asked to motivate their classmates to drink water during eight weeks. The experimenters offer them support at two follow-up sessions one and four weeks after the training.