Twenty Rhode Island high schools agreed to participate in the study. A Multiattribute Utility Measurement Approach (Graham, Flay, Johnson, Hansen, & Collins, 1984) was used to ensure that schools assigned to the intervention and comparison conditions were approximately equivalent on school size, student ethnicity, socioeconomic status (SES, percent receiving free or reduced-price lunch), attendance, mobility, truancy, dropout, and standardized test performance. The most similar schools were paired, and one school within each pair was randomly assigned to intervention, and the other to comparison.
The intervention trial was launched in the Fall of 2009. Both the intervention and comparison groups completed a computerized baseline assessment and two follow-up assessments approximately 6 and 12 months later-in the Spring and Fall of 2010. Students assigned to the intervention condition completed their first Teen Choices intervention session immediately following their baseline assessment. The second and third intervention sessions were administered at approximately 1 and 2 months follow-up. Students assigned to the comparison condition completed an alternative evidence-based online TTM-based intervention, Health In Motion, which targets physical activity, screen time, and healthy eating for obesity prevention (Mauriello et al., 2010). Health In Motion sessions were administered following the baseline, 6-month, and 12-month assessments to increase the benefits of study participation for comparison schools and students. Online assessment and intervention sessions were overseen by project research assistants with the assistance of school personnel.
Dating violence outcomes at one year follow-up were were examined in intervention and comparison participants who completed the final assessment and were exposed to risk for dating violence-that is, students who had experienced or perpetrated emotional or physical dating violence in the year prior to the study, who were current daters at baseline, or who dated during the follow-up period. Peer violence outcomes were examined in participants who completed the final assessment and were not exposed to risk for dating violence.