Effectiveness of an educational intervention based on theory of planned behavior to reduce intentions to smoke among secondary school students

Beliefs about smoking are important predictors of smoking behavior among adolescents. An alarming fact is the rising smoking prevalence in Asian countries especially in the Middle East, particularly the increasing trend in smoking during adolescence. In a randomized controlled trial study, 150 students e were selected using multistage sampling procedure from boy-specific high schools in Qazvin. A self constructed questionnaire was administered consisting of demographic and the theory of Planned Behavior (TPB) constructs (i.e. attitudes towards smoking, subjective norms, perceived behavioral control and intention to smoke. The adolescents were asked to complete the questionnaire at the baseline and then they were randomly assigned either experimental (n=75) or control group (n=75). The randomization unit was the school. Adolescents in the experimental group received four educational sessions during three weeks while those in the control group did not receive any kind of intervention. The data was collected at baseline and three months after the intervention. The average age of the adolescents was 15.3±0.62. Approximately, 1% and 7.6% of the adolescents had a mother and father who had smoke, respectively. There was no difference between control and experiential groups in terms of demographic variables. The educational intervention resulted in improving for attitudes, subjective norms, perceived behavioral control and intention in the experimental group in comparison with the control group. Furthermore, preventive smoking behavior was increased significantly among adolescents in the experimental group in comparison with those the control group. The results suggest that an intervention based on the TPB to prevent smoking behaviors can bring about promising results among adolescents.