@Article{info:doi/10.2196/jmir.2469, author="de Josselin de Jong, Sanne and Candel, Math and Segaar, Dewi and Cremers, Henricus-Paul and de Vries, Hein", title="Efficacy of a Web-Based Computer-Tailored Smoking Prevention Intervention for Dutch Adolescents: Randomized Controlled Trial", journal="J Med Internet Res", year="2014", month="Mar", day="21", volume="16", number="3", pages="e82", keywords="computer tailoring; Web-based intervention; Internet; smoking prevention; smoking initiation; adolescents; randomized controlled trial", abstract="Background: Preventing smoking initiation among adolescents is crucial to reducing tobacco-caused death and disease. This study focuses on the effectiveness of a Web-based computer-tailored smoking prevention intervention aimed at adolescents. Objective: The intent of the study was to describe the intervention characteristics and to show the effectiveness and results of a randomized controlled trial. We hypothesized that the intervention would prevent smoking initiation among Dutch secondary school students aged 10-20 years and would have the largest smoking prevention effect among the age cohort of 14-16 years, as smoking uptake in that period is highest. Methods: The intervention consisted of a questionnaire and fully automated computer-tailored feedback on intention to start smoking and motivational determinants. A total of 89 secondary schools were recruited via postal mail and randomized into either the computer-tailored intervention condition or the control condition. Participants had to complete a Web-based questionnaire at baseline and at 6-month follow-up. Data on smoking initiation were collected from 897 students from these schools. To identify intervention effects, multilevel logistic regression analyses were conducted using multiple imputation. Results: Smoking initiation among students aged 10-20 years was borderline significantly lower in the experimental condition as compared to the control condition 6 months after baseline (OR 0.25, 95{\%} CI 0.05-1.21, P=.09). Additional analyses of the data for the 14-16 year age group showed a significant effect, with 11.5{\%} (24/209) of the students in the control condition reporting initiation compared to 5.7{\%} (10/176) in the experimental condition (OR 0.22, 95{\%} CI 0.05-1.02, P=.05). No moderation effects were found regarding gender and educational level. Conclusions: The findings of this study suggest that computer-tailored smoking prevention programs are a promising way of preventing smoking initiation among adolescents for at least 6 months, in particular among the age cohort of 14-16 years. Further research is needed to focus on long-term effects. Trial Registration: International Standard Randomized Controlled Trial Number (ISRCTN): 77864351; http://www.controlled-trials.com/ISRCTN77864351 (Archived by WebCite at http://www.webcitation.org/6BSLKSTm5). ", issn="14388871", doi="10.2196/jmir.2469", url="http://www.jmir.org/2014/3/e82/", url="https://doi.org/10.2196/jmir.2469", url="http://www.ncbi.nlm.nih.gov/pubmed/24657434" }