Effectiveness of a complex intervention in reducing the prevalence of smoking among adolescents: study design of a cluster-randomized controlled trial

Alfonso Leiva, Andreu Estela, Maties Torrent, Amador Calafat, Miquel Bennasar, Aina Yáñez, Alfonso Leiva, Andreu Estela, Maties Torrent, Amador Calafat, Miquel Bennasar, Aina Yáñez

Abstract

Background: The likelihood of an adolescent taking up smoking may be influenced by his or her society, school and family. Thus, changes in the immediate environment may alter a young person's perception of smoking.

Methods/design: The proposed multi-center, cluster-randomized controlled trial will be stratified by the baseline prevalence of smoking in schools. Municipalities with fewer than 100,000 inhabitants will be randomly assigned to a control or intervention group. One secondary school will be randomly selected from each municipality. These schools will be randomized to two groups: the students of one will receive any existing educational course regarding smoking, while those of the other school will receive a four-year, class-based curriculum intervention (22 classroom lessons) aimed at reinforcing a smoke-free school policy and encouraging smoking cessation in parents, pupils, and teachers. The intervention will also include annual meetings with parents and efforts to empower adolescents to change the smoking-related attitudes and behaviors in their homes, classrooms and communities.We will enroll children aged 12-13 years as they enter secondary school during two consecutive school years (to obtain sufficient enrolled subjects). We will follow them for five years, until two years after they leave secondary school. All external evaluators and analysts will be blinded to school allocation.The aim of this study is to analyze the effectiveness of a complex intervention in reducing the prevalence of smoking in the third year of compulsory secondary education (ESO) and two years after secondary school, when the participants are 14-15 and 17-18 years old, respectively.

Discussion: Most interventions aimed at preventing smoking among adolescents yield little to no positive long-term effects. This clinical trial will analyze the effectiveness of a complex intervention aimed at reducing the incidence and prevalence of smoking in this vulnerable age group.

Trial registration: Current Controlled Trials: NCT01602796.

References

    1. Peto R, Lopez AD, Boreham J, Thun M, Heath C Jr, Doll R. Mortality from smoking worldwide. Br Med Bull. 1996;52:12–21. doi: 10.1093/oxfordjournals.bmb.a011519.
    1. The world health report 2002 - Reducing risks, promoting healthy life. The world health report 2002 - Reducing risks, promoting healthy life. Geneva: World Health Organization; 2002. , accessed 10 May 2010.
    1. Hublet A, De BD, Valimaa R, Godeau E, Schmid H, Rahav G, Maes L. Smoking trends among adolescents from 1990 to 2002 in ten European countries and Canada. BMC Public Health. 2006;6:280. doi: 10.1186/1471-2458-6-280.
    1. Ali SM, Chaix B, Merlo J, Rosvall M, Wamala S, Lindstrom M. Gender differences in daily smoking prevalence in different age strata: a population-based study in southern Sweden. Scand J Pub Health. 2009;37:146–152. doi: 10.1177/1403494808100274.
    1. Azevedo A, Machado AP, Barros H. Tobacco smoking among Portuguese high-school students. Bull World Health Organ. 1999;77:509–514.
    1. Aveyard P, Markham WA, Cheng KK. A methodological and substantive review of the evidence that schools cause pupils to smoke. Soc Sci Med. 2004;58:2253–2265. doi: 10.1016/j.socscimed.2003.08.012.
    1. Yanez AM, Lopez R, Serra-Batlles J, Roger N, Arnau A, Roura P. Smoking among adolescents: population study on parental and school influences. Arch Bronconeumol. 2006;42:21–24.
    1. Flay BR. Understanding environmental, situational and intrapersonal risk and protective factors for youth tobacco use: the Theory of Triadic Influence. Nicotine Tob Res. 1999;1(Suppl 2):S111–S114.
    1. Khuder SA, Dayal HH, Mutgi AB. Age at smoking onset and its effect on smoking cessation. Addict Behav. 1999;24:673–677. doi: 10.1016/S0306-4603(98)00113-0.
    1. Muller-Riemenschneider F, Bockelbrink A, Reinhold T, Rasch A, Greiner W, Willich SN. Long-term effectiveness of behavioural interventions to prevent smoking among children and youth. Tob Control. 2008;17:301–302. doi: 10.1136/tc.2007.024281.
    1. Ariza C, Nebot M. La prevención del tabaquismo en los jóvenes: realidades y retos para el futuro. Adicciones. 2004;16:359–378.
    1. Comin BE, Torrubia BR, Mor SJ, Villalbi H Jr, Nebot AM. The reliability of a self-administered questionnaire for investigation of the level of exercise, smoking habit and alcohol intake in school children. Med Clin (Barc ) 1997;108:293–298.
    1. Yañez A, Leiva A, Gorreto L, Estela A, Tejera E, Torrent M. School, family and adolescent smoking. Adicciones. 2013;25:37–44.
    1. Siddiqui O, Hedeker D, Flay BR, Hu FB. Intraclass correlation estimates in a school-based smoking prevention study. Outcome and mediating variables, by sex and ethnicity. Am J Epidemiol. 1996;144:425–433. doi: 10.1093/oxfordjournals.aje.a008945.
    1. Nebot M, Tomas Z, Ariza C, Valmayor S, Lopez MJ, Juarez O. Factors Associated With Smoking Onset: 3-Year Cohort Study of Schoolchildren. Arch Bronconeumol. 2004;40:495–501.
    1. Ariza-Cardenal C, Nebot-Adell M. Factors associated with smoking progression among Spanish adolescents. Health Educ Res. 2002;17:750–760. doi: 10.1093/her/17.6.750.
    1. Ariza-Cardenal C, Nebot-Adell M. Predictors of the onset of tobacco consumption among secondary school students of Barcelona and Lleida. Rev Esp Salud Publica. 2002;76:227–238. doi: 10.1590/S1135-57272002000300007.
    1. Tomas Z, Ariza C, Valmayor S, Mudde A, Nebot M. [Factors associated with smoking and the intention to smoke in secondary school pupils: results of the ESFA project in Barcelona, Spain] Gac Sanit. 2002;16:131–138. doi: 10.1016/S0213-9111(02)71644-0.
    1. Peterson AV Jr, Kealey KA, Mann SL, Marek PM, Sarason IG. Hutchinson Smoking Prevention Project: long-term randomized trial in school-based tobacco use prevention–results on smoking. J Natl Cancer Inst. 2000;92:1979–1991. doi: 10.1093/jnci/92.24.1979.
    1. Perry CL, Kelder SH, Murray DM, Klepp KI. Communitywide smoking prevention: long-term outcomes of the Minnesota Heart Health Program and the Class of 1989 Study. Am J Public Health. 1992;82:1210–1216. doi: 10.2105/AJPH.82.9.1210.
    1. Vartiainen E, Paavola M, McAlister A, Puska P. Fifteen-year follow-up of smoking prevention effects in the North Karelia youth project. Am J Public Health. 1998;88:81–85. doi: 10.2105/AJPH.88.1.81.
    1. Aveyard P, Cheng KK, Almond J, Sherratt E, Lancashire R, Lawrence T, Griffin C, Evans O. Cluster randomised controlled trial of expert system based on the transtheoretical (“stages of change”) model for smoking prevention and cessation in schools. BMJ. 1999;319:948–953. doi: 10.1136/bmj.319.7215.948.
    1. Ellickson PL, Bird CE, Orlando M, Klein DJ, McCaffrey DF. Social context and adolescent health behavior: does school-level smoking prevalence affect students’ subsequent smoking behavior? J Health Soc Behav. 2003;44:525–535. doi: 10.2307/1519797.
    1. Armstrong BK, de Klerk NH, Shean RE, Dunn DA, Dolin PJ. Influence of education and advertising on the uptake of smoking by children, 19. Med J Aust. 1990;152:117–124.
    1. Brown KS, Cameron R, Madill C, Payne ME, Filsinger S, Manske SR, Best JA. Outcome evaluation of a high school smoking reduction intervention based on extracurricular activities. Prev Med. 2002;35:506–510. doi: 10.1006/pmed.2002.1097.
    1. Wen X, Chen W, Muscat JE, Qian Z, Lu C, Zhang C, Luo Y, Liang C, Han K, Deng X, Ou Y, Ling W. Modifiable family and school environmental factors associated with smoking status among adolescents in Guangzhou, China. Prev Med. 2007;45:189–197. doi: 10.1016/j.ypmed.2007.02.009.
    1. Wakefield MA, Chaloupka FJ, Kaufman NJ, Orleans CT, Barker DC, Ruel EE. Effect of restrictions on smoking at home, at school, and in public places on teenage smoking: cross sectional study. BMJ. 2000;321:333–337. doi: 10.1136/bmj.321.7257.333.

Source: PubMed

3
Sottoscrivi