PT  - JOURNAL ARTICLE
AU  - Linnea Hedman
AU  - Martin Andersson
AU  - Caroline Stridsman
AU  - Eva Rönmark
TI  - Selection bias in participation in a smoking prevention program among teenagers
DP  - 2014 Sep 01
TA  - European Respiratory Journal
PG  - P1125
VI  - 44
IP  - Suppl 58
4099  - http://erj.ersjournals.com/content/44/Suppl_58/P1125.short
4100  - http://erj.ersjournals.com/content/44/Suppl_58/P1125.full
SO  - Eur Respir J2014 Sep 01; 44
AB  - Background: Reducing smoking in teenagers is an important public health intervention. Many prevention efforts are voluntary and participation may be affected by selection bias.Aim: to compare participants and non-participants in a voluntary smoking prevention program in teenagers.Method: Within the Obstructive Lung Disease in Northern Sweden (OLIN) studies, a population-based study of asthma and allergic diseases in schoolchildren started in 2006. In 2010, a questionnaire about asthma, allergic diseases and potential risk factors was completed at age 11-12y (n=2612, 95% of invited). A voluntary smoking prevention program in the study area invited a sample of the OLIN cohort (n=466) and 229 (49%) chose to participate.Results: Among the non-participants, the prevalence of boys (59% vs. 43%, p<0.001), having a smoking mother (20% vs. 9%, p<0.001) and living in a single parent household (16% vs. 8%, p<0.008) was higher than among participants. Fewer non-participants were doing sports (65% vs. 79%, p<0.002) and parental socioeconomic status (SES) was lower among non-participants (test-for-trend p<0.005). In a multivariate analysis, factors related to non-participation were male sex (OR 1.8 95%CI 1.2-2.7), having a smoking mother (OR 2.1 95%CI 1.1-3.8), parental SES (OR 3.0 95%CI 1.3-6.7 for manual workers in service), and participation in sports (OR 0.6 95%CI 0.3-0.9).Conclusion: A selection bias was found as those in most need of smoking prevention, i.e. children having smoking parents and a lower SES, did not participate in the program.