title: Psychological predictors of male smokeless tobacco use initiation and cessation: a 16-year longitudinal study.
abstract: OBJECTIVE
  To test whether psychological factors predict male smokeless tobacco (SLT) initiation and cessation longitudinally.
  
  
  METHODS
  Sixteen-year longitudinal design with 95% retention at year 6 and 82% at year 16.
  
  
  METHODS
  Forty Washington State school districts.
  
  
  METHODS
  SLT use data were gathered on a cohort of adolescents (91% Caucasian). For SLT initiation, the sample size was 2468. For SLT cessation, sample sizes were 219 (age 20 outcome) and 192 (age 28 outcome).
  
  
  METHODS
  Self-reported psychological measures of parental disobedience ('parent non-compliance'), peer influence ('friend compliance'), rebelliousness and thrill-seeking were taken at ages 12 and 18. SLT use was measured at ages 12, 18, 20 and 28 years.
  
  
  RESULTS
  For SLT initiation, scoring highly on the following psychological factors at age 12 at least doubled the odds of daily SLT use at age 18 (P < 0.001): friend compliance [odds ratio (OR): 2.56, 95% confidence interval (CI): 1.78-3.68), rebelliousness (OR: 2.16, 95% CI: 1.46-3.19) and thrill-seeking (OR: 2.33, 95% CI: 1.45-3.75). For SLT cessation, none of the psychological factors at age 18 predicted SLT cessation at age 20 or 28 (P value range: 0.06-0.84).
  
  
  CONCLUSIONS
  Peer influence, rebelliousness, and thrill-seeking appear to predict smokeless tobacco initiation strongly among male youth in the United States.
authors.affiliation: Cancer Prevention Research Program, Division of Public Sciences, Fred Hutchinson Cancer Research Center, Seattle, WA 98109-1024, USA.
authors.forename: Leela R
authors.initials: LR
authors.lastname: Holman
authors.forename: Jonathan B
authors.initials: JB
authors.lastname: Bricker
authors.forename: Bryan A
authors.initials: BA
authors.lastname: Comstock
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D002648:Child; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D010287:Parent-Child Relations; D010379:Peer Group; D012307:Risk Factors; D012309:Risk-Taking; D012463:Saliva / Q000737:chemistry; D057566:Self Report; D012907:Smoking / Q000453:epidemiology / Q000523:psychology*; D016540:Smoking Cessation / Q000523:psychology*; D012931:Social Environment; D014030:Tobacco, Smokeless / Q000706:statistics & numerical data*; D014861:Washington / Q000453:epidemiology; D055815:Young Adult