title: Psychosocial predictors of smoking trajectories during middle and high school.
abstract: OBJECTIVE
  Little is known about the heterogeneity in and risk factors associated with trajectories of smoking during adolescence. This study aimed to (1) identify smoking trajectories empirically and (2) identify risk factors for trajectory group membership.
  
  
  METHODS
  Latent growth mixture models were used to identify population smoking trajectories, and logistic regression was used to estimate risk factors for group membership.
  
  
  METHODS
  The participants were drawn from seven middle schools in a Maryland school district.
  
  
  METHODS
  Participants consisted of 1320 6th graders who were followed to the 9th grade.
  
  
  METHODS
  Measurements of smoking risk factors were made in the fall of 6th grade and smoking stage was assessed on five different occasions between the fall of 6th and 9th grades.
  
  
  RESULTS
  Five distinct smoking trajectories were identified. Overall, being female, having friends who smoked, deviance acceptance and outcome expectations were associated with an increased likelihood of being an intender, delayed escalator, early experimenter and early user compared to a never smoker. Additionally, comparisons with never smokers revealed unique identifiers for intenders, early experimenters and early users, but not delayed escalators.
  
  
  CONCLUSIONS
  There is much heterogeneity in the manner in which middle-schoolers progress from having no intention of smoking to becoming smokers. Implications for prevention programs are discussed.
authors.affiliation: Department of Prevention and Community Health, School of Public Health and Health Services, George Washington University Medical Center, Washington, DC 20037, USA. sphlca@gwumc.edu
authors.forename: Lorien
authors.initials: L
authors.lastname: Abroms
authors.forename: Bruce
authors.initials: B
authors.lastname: Simons-Morton
authors.forename: Denise L
authors.initials: DL
authors.lastname: Haynie
authors.forename: Rusan
authors.initials: R
authors.lastname: Chen
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior / Q000523:psychology*; D005260:Female; D005544:Forecasting; D006801:Humans; D016015:Logistic Models; D008297:Male; D008396:Maryland; D008962:Models, Theoretical; D010379:Peer Group; D012307:Risk Factors; D012907:Smoking / Q000523:psychology*; D012919:Social Behavior; D011795:Surveys and Questionnaires