Effects of a social-network method for group assignment strategies on peer-led tobacco prevention programs in schools

Objectives. Our study tested the effectiveness of network methods for identifying opinion leaders and for constructing groups. Methods. Three conditions-random, teacher, and network-were randomly assigned to 84 6th-grade classrooms within 16 schools. Pre- and postcurriculum data on mediators of tobacco use were collected from 1961 students. Peer leaders in the network condition were identified by student nominations, and those leaders were matched with the students who nominated them. Results. Students in the network condition relative to the random condition liked the prevention program more and had improved attitudes (beta=-0.06; P<.01), improved self-efficacy (beta=-0.10; P<.001), and decreased intention to smoke (adjusted odds ratio [OR] = 0.46; 95% confidence interval [CI] = 0.38, 0.55). Conclusions. The network method was the most effective way to structure the program. Future programs may refine this technique and use it in other settings.