title: Individual and city-level determinants of secondhand smoke exposure in China.
abstract: BACKGROUND
  Second hand smoke (SHS) exposure is a severe public health problem, especially in low and middle countries, but no studies have examined both individual and city-level variables influencing exposure.
  
  
  METHODS
  A cross-sectional multistage sampling design was used to survey subjects from 21 cities in China. Using a standardized questionnaire individual level information was collected. City-level variables were retrieved from the National Bureau of Statistics database. Multilevel logistic regression analysis was used to assess SHS exposure variation at both the individual and city level.
  
  
  RESULTS
  SHS exposure prevalence among non-smokers was 28.1% (95% CI 27.1-29.0). At the individual level lower educational attainment and income and higher exposure to tobacco advertising were associated with higher SHS exposure. On the other hand richer cities, and those with more anti-smoking media news coverage, had less SHS exposure. The presence of city smokefree regulations was unrelated to exposure.
  
  
  CONCLUSIONS
  Given its human and economic costs, reducing SHS exposure should receive greater priority than it does in China. The results point to the need for the enactment of national smokefree laws in order to combat unacceptably high levels of SHS exposure.
authors.affiliation: Center for Tobacco Control Research, Zhejiang University School of Medicine, Yuhangtang Road, Hangzhou, 310058, China. Tingzhongyang@zju.edu.cn.
authors.forename: Tingzhong
authors.initials: T
authors.lastname: Yang
authors.affiliation: Center for Tobacco Control Research, Zhejiang University School of Medicine, Yuhangtang Road, Hangzhou, 310058, China. shuhan_jiang@163.com.
authors.forename: Shuhang
authors.initials: S
authors.lastname: Jiang
authors.affiliation: Department of Geography, University of Canterbury, Christchurch, 8140, New Zealand. ross.barnett@canterbury.ac.nz.
authors.forename: Ross
authors.initials: R
authors.lastname: Barnett
authors.affiliation: Center for Tobacco Control Research, Zhejiang University School of Medicine, Yuhangtang Road, Hangzhou, 310058, China. psh_zx_zxx@163.com.
authors.forename: Sihui
authors.initials: S
authors.lastname: Peng
authors.affiliation: Center for Tobacco Control Research, Zhejiang University School of Medicine, Yuhangtang Road, Hangzhou, 310058, China. yulw2011@sina.com.
authors.forename: Lingwei
authors.initials: L
authors.lastname: Yu
mesh_terms: D000328:Adult; D000329:Advertising / Q000706:statistics & numerical data; D016009:Chi-Square Distribution; D002681:China / Q000453:epidemiology; D002947:Cities / Q000706:statistics & numerical data; D003430:Cross-Sectional Studies; D004781:Environmental Exposure / Q000517:prevention & control / Q000706:statistics & numerical data*; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D008297:Male; D055361:Multilevel Analysis; D015995:Prevalence; D057566:Self Report; D017678:Sex Distribution; D012959:Socioeconomic Factors; D011795:Surveys and Questionnaires; D019460:Tobacco Industry / Q000191:economics / Q000706:statistics & numerical data*; D014028:Tobacco Smoke Pollution / Q000517:prevention & control / Q000706:statistics & numerical data*; D055815:Young Adult
chemical_list: D014028:Tobacco Smoke Pollution