Abstract

This study investigated longitudinally the extent to which childhood friends who smoke influence adolescents' smoking transitions, and compared that influence with that of parents who smoke. In a sample of 4744 children, results showed that the probability, per close friend, that a smoking close friend influenced the adolescent to make the first transition to trying smoking was 38% (95% CI: 28%, 46%); to make the second transition from trying to monthly smoking, 10% (95% CI: 5%, 15%); and to make the third transition from monthly to daily smoking, 11% (95% CI: 5%, 17%). Compared to parents' smoking, close friends' smoking was 12% (p = 0.03) more influential for the first transition, no different for the second transition (p = 0.53), and 16% (p = 0.01) less influential for the third transition. Results provide new evidence suggesting that childhood close friends who smoke influence not only initiation but also escalation of adolescents' smoking. Results also confirmed the important role of parents' smoking. Targeting both childhood close friends' and parents' smoking would be valuable in prevention research.

Keywords: Friends; Parents; Children; Adolescents; Smoking transitions

Article Outline

1. Introduction

1.1. Adolescents' smoking transitions

1.2. How much influence should close friends have on adolescent smoking transitions?

1.3. Close friends versus parents

1.4. This study

2. Methods

2.1. Study sample

2.2. Procedures

2.3. Measures

2.3.1. Parents' smoking status when adolescent was in third grade

2.3.2. Close friends' smoking status when adolescent was in fifth grade

2.3.3. Smoking transitions of cohort members

2.4. The social transmission probability model

2.5. Fitting the model

3. Results

3.1. Close friends', parents', and adolescents' smoking

3.1.1. Probabilities of transmission from close friend(s) to adolescent

3.1.2. Probabilities of transmission from parent to adolescent

3.1.3. Comparison of the probabilities of transmission from close friends versus parents

3.1.4. Comparison of probabilities of transmission from parents and close friends versus other sources

3.2. Observed and model-fitted probabilities from the social epidemic model

4. Discussion

4.1. Quantification of the influence of childhood friends' smoking on adolescent smoking transitions

4.2. Hypothesis regarding the influence of childhood friends' smoking versus parents' smoking on adolescent smoking transitions

4.3. The combined role of childhood friends' and parents' smoking

4.4. Public health implications

4.5. Limitations

4.6. Conclusion

Acknowledgements

References