A summary of the BROMS cohort study

A summary of the BROMS cohort studyThe BROMS Cohort Study (Swedish acronym for Children’s Smoking and Environment inthe Stockholm County) is a longitudinal study with the purpose to assess determinants ofuptake of tobacco use.The cohort:The cohort participants were recruited in the school-year 1997-1998 through a weightedrandom sample of schools with fifth-grade students in the Stockholm region. Followingparental consent, 3,050 students (65%) were enrolled and 3,020 completed the baselineassessment (1,537 boys and 1,483 girls, mean age 11.6 years). The students were invited toparticipate in a similar annual survey up to the age of 15 years (four follow-up waves duringcompulsory school education). Thereafter, two further follow-up surveys were conducted, atthe ages of 17 and 18 years. The participation rate ranged from 96% (at follow-up 1, age 12)to 82% (at follow-up 6, age 18). The proportion participating in all follow-up waves was 69%.Available information:The information on smoking behaviour and use of snus was collected by means of a selfcompletedquestionnaire administered in the classroom, or mailed directly to the students’homes (last two surveys). At each wave of data collection, past and current cigarette smokingand snus use were investigated with a set of almost identical questions. Information includedage at initiation, symptoms at first use, attempts to quit, desire to quit, symptoms experiencedduring quit attempts, circumstances of tobacco use and preferred brand. In addition, thequestionnaire encompassed questions on potential explanatory factors of tobacco use (e.g.parents’ and friends’ tobacco use, relation to school, health related behaviours) and sociodemographiccharacteristics. Self-reported tobacco use showed high reliability whencompared to saliva cotinine, in a sub-sample of the cohort. Information about the schools andclasses attended by each student was collected at baseline from the school principal and theclass teacher, respectively. Anthropometric measures and summary medical history wascollected by the school nurses annually between grade five and eight.Publications based on data from the BROMS cohort:Caria, M. P. (2007). Statistical models for longitudinal data: an application to a cohort ofadolescents for the relationship between body mass index and smoking. Master thesis,Department of Statistics, University of Milano-Bicocca.Caria, M. P., Bellocco, R., Zambon, A., Horton, N. J., & Galanti, M. R. (2009). Overweightand perception of overweight as predictors of smokeless tobacco use and of cigarette smokingin a cohort of Swedish adolescents. Addiction, 104, 661-668.Galanti, M. R., Rosendahl, I., Post, A., & Gilljam, H. (2001). Early gender differences inadolescent tobacco use – The experience of a Swedish cohort. Scand J Public Health, 29,314-317.

Galanti, M. R., Rosendahl, I., & Wickholm, S. (2008). The development of tobacco use inadolescence among “snus starters” and “cigarette starters”: An analysis of the Swedish“BROMS” cohort. Nicotine & Tobacco Research, 10, 315-323.Post, A. (2009). Issues of validity in longitudinal studies of youth tobacco use. Doctoraldissertation. The Department of Public Health Sciences, Karolinska Institutet, Stockholm,Sweden.Post, A., Galanti, M. R., & Gilljam, H. (2003). School and family participation in alongitudinal study of tobacco use. Some methodological notes. European Journal of PublicHealth, 13, 75-76.Post, A., Gilljam, H., Bremberg, S., & Galanti, M. R. (2008). Maternal smoking duringpregnancy: a comparison between concurrent and retrospective self-reports. Paediatric andPerinatal Epidemiology, 22, 155-161.Post, A., Gilljam, H., Rosendahl, I., Bremberg, S., & Galanti, M. R. (In press). Symptoms ofnicotine dependence in a cohort of Swedish youths: a comparison between smokers,smokeless tobacco users and dual tobacco users.Post, A., Gilljam, H., Rosendahl, I., Meurling, L., Bremberg, S., & Galanti, M. R. (2005).Validity of self reports in a cohort of Swedish adolescent smokers and smokeless tobacco(snus) users. Tobacco Control, 14, 114-117.Rosendahl, I. (2005). Modeling individual behavioral changes: the case of tobacco uptake ina cohort of school children. Doctoral dissertation. The Division of Epidemiology, Institute ofEnvironmental Medicine, Karolinska Institutet, and Stockholm Centre for Public Health –Tobacco Prevention, Stockholm, Sweden.Rosendahl, K. I., Galanti, M. R., Gilljam, H., & Ahlbom, A. (2003). Smoking mothers andsnuffing fathers: behavioural influences on youth tobacco use in a Swedish cohort. TobaccoControl, 12, 74-78.Rosendahl, K. I., Galanti, M. R., Gilljam, H., & Ahlbom, A. (2005). Knowledge abouttobacco and subsequent use of cigarettes and smokeless tobacco among Swedish adolescents.Journal of Adolescent Health, 37, 224-228.Rosendahl, K. I., Galanti, M. R., Gilljam, H., Bremberg, S., & Ahlbom, A. (2002). School andclass environments are differently linked to future smoking among preadolescents. PreventiveMedicine, 34, 649-654.