title: Socioeconomic status and smokers' number of smoking friends: findings from the International Tobacco Control (ITC) Four Country Survey.
abstract: BACKGROUND
  Smoking rates are higher among low socioeconomic (SES) groups, and there is evidence that inequalities in smoking are widening over time in many countries. Low SES smokers may be more likely to smoke and less likely to quit because smoking is heavily concentrated in their social contexts. This study investigated whether low SES smokers (1) have more smoking friends, and (2) are more likely to gain and less likely to lose smoking friends over time. Correlates of having more smoking friends and gaining or losing smoking friends were also considered.
  
  
  METHODS
  Respondents included 6321 adult current smokers (at recruitment) from Wave 1 (2002) and Wave 2 (2003) of the International Tobacco Control Project (ITC) Four Country Survey, a nationally representative longitudinal cohort survey of smokers in Australia, Canada, UK, and US.
  
  
  RESULTS
  Low SES smokers reported more smoking friends than moderate and high SES smokers. Low SES smokers were also more likely to gain smoking friends over time compared with high SES smokers. Smokers who were male, younger, and lived with other smokers reported more smoking friends, and were also more likely to gain and less likely to lose smoking friends. Smoking behaviours, such as higher nicotine dependence were related to reporting more smoking friends, but not to losing or gain smoking friends.
  
  
  CONCLUSIONS
  Smoking is highly concentrated in the social networks of lower SES smokers and this concentration may be increasing over time. Cessation interventions should consider how the structure of low SES smokers' social networks affects quitting.
authors.affiliation: Department of Addictions, Institute of Psychiatry, King's College London, 4 Windsor Walk, London SE5 8BB, United Kingdom. Electronic address: sara.hitchman@kcl.ac.uk.
authors.forename: Sara C
authors.initials: SC
authors.lastname: Hitchman
authors.affiliation: School of Public Health and Health Systems, University of Waterloo, 200 University Avenue West, Waterloo, ON, Canada N2L 3G1; Department of Psychology, University of Waterloo, 200 University Avenue West, Waterloo, ON, Canada N2L 3G1; Ontario Institute for Cancer Research, 101 College Street, Toronto, ON, Canada M5G 1L7.
authors.forename: Geoffrey T
authors.initials: GT
authors.lastname: Fong
authors.affiliation: Department of Psychology, University of Waterloo, 200 University Avenue West, Waterloo, ON, Canada N2L 3G1.
authors.forename: Mark P
authors.initials: MP
authors.lastname: Zanna
authors.affiliation: Department of Health Promotion, Education, and Behavior, Arnold School of Public Health, University of South Carolina, 800 Sumter Street, Columbia, SC 29208, United States.
authors.forename: James F
authors.initials: JF
authors.lastname: Thrasher
authors.affiliation: Department of Psychology, University of Waterloo, 200 University Avenue West, Waterloo, ON, Canada N2L 3G1.
authors.forename: Janet
authors.initials: J
authors.lastname: Chung-Hall
authors.affiliation: College of Public Health, University of Nebraska Medical Center, 984365 Nebraska Medical Center , Omaha, NE 68198-4355, United States.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Siahpush
mesh_terms: D000293:Adolescent; D000328:Adult; D003431:Cross-Cultural Comparison; D005260:Female; D033062:Friends / Q000523:psychology*; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D012907:Smoking / Q000453:epidemiology* / Q000523:psychology*; D016540:Smoking Cessation / Q000523:psychology* / Q000706:statistics & numerical data; D012932:Social Facilitation; D012959:Socioeconomic Factors; D013223:Statistics as Topic; D055815:Young Adult
keywords: Smoking cessation; Social context; Social network; Socioeconomic inequalities