Longitudinal evaluation of a smoking prevention program for adolescents

To evaluate a smoking prevention program for adolescents.The program was conducted between 1999 and 2002, in schools of the district of Lisbon, Portugal. The program integrated activities in the school, family and community. This was a longitudinal quasi-experimental study, based on Community Intervention Trial, with randomly defined control conditions (CC) and intervention conditions (IC). A total of four questionnaires were applied in the beginning of the 7th(T1), 8th(T2) and 9th(T3) and in the end of the 9th(T4) school grades, to 1,205 adolescents, aged 13 years on average, of which 57% were girls and 55% were included in the IC. Exposure to prevention activities, psychosocial determinants of smoking and behavior were the variables considered in the evaluation of the program. Variance analysis and logistic regression were used to test the differences between the two study conditions.IC obtained better results in the smoking psychosocial determinants and in behavior. At the end of the project, 41.8% of participants in the IC and 53.3% of those in the CC had tried tobacco (OR = 0.62; CI95% 0.49;0.80), while those who became regular smokers totaled 8.0% and 12.4%, respectively (OR = 0.59; CI95% 0.40;0.87).The program reduced the initiation of smoking and regular smoking. Results appeared in the second year and improved in the third. Effectiveness of smoking prevention programs depends on a continuous implementation throughout adolescence and on the integration of measures aimed to reach adolescents directly and indirectly through their social context (school, family and community).