Eight-year follow-up results of an adolescent smoking prevention program: the North Karelia Youth Project.

Abstract
In the North Karelia Youth Program five to 10 classroom sessions over two years taught skills to resist pressures to start smoking to 13 to 15 year old students. Compared to students from comparison schools, the treatment groups reported less smoking immediately after the intervention and in a four-year follow-up survey. At the eight-year follow-up, there was consistent evidence of possible preventive effects only among those who had been non-smokers when the program began.