Reducing smoking in youth by a smoke-free school environment: A stratified cluster randomized controlled trial of Focus, a multicomponent program for alternative high schools.

Youth smoking remains a major challenge for public health. Socioeconomic position influences the initiation and maintenance of smoking, and alternative high school students are at particularly high risk. The school environment is an important setting to promote health, however there is a lack of evidence-based school intervention programs. This article presents the Focus study, which aims to test the implementation and effectiveness of a school-based intervention integrating a comprehensive school smoking policy [i.e. smoke-free school hours (SFSH)], a course for school staff in short motivational conversations, school class-based teaching material, an edutainment session5, a class-based competition, and6 access to smoking cessation support. Together these intervention components address students' acceptability of smoking, social influences, attitudes, motivation, and opportunities for smoking. The setting is alternative high schools across Denmark, and the evaluation design is based on a stratified cluster randomized controlled trial comparing the intervention group to a control group. Outcome data is collected at baseline, midway, and at the end of the intervention period. Moreover, a detailed process evaluation, using qualitative and quantitative methods, is conducted among students, teachers, and school principals. The results from this trial will provide important knowledge on the effectiveness of a smoke-free school environment. The findings will lead to a better understanding of which policies, environments, and cognitions, contribute to preventing and reducing cigarette use among young people in a diverse and high-risk school setting, and illuminate which complementary factors are significant to achieve success when implementing SFSH.