title: Hidden female smokers in Asia: a comparison of self-reported with cotinine-verified smoking prevalence rates in representative national data from an Asian population.
abstract: BACKGROUND
  The low smoking prevalence in Asian women may be due to under-reporting. We therefore investigated gender difference in self-reported and cotinine-verified smoking prevalence rates in Korea
  
  
  METHODS
  We analysed data from 5455 individuals (2387 men and 3068 women) in the 2008 Korean National Health and Nutrition Examination Survey. A urinary cotinine concentration of 50 ng/ml was the cut-off distinguishing smokers from non-smokers. Sensitivity analysis was done using different cut-offs of 25, 75 and 100 ng/ml.
  
  
  RESULTS
  Cotinine-verified smoking rates were 50.0% for men and 13.9% for women, or 5.3% point and 8.0% point higher in absolute terms, respectively, than the self-reported rates for men and women. Ratios of cotinine-verified to self-reported smoking rates were 2.36 for women and 1.12 for men. Of the 1620 cotinine-verified smokers, 12.1% of men and 58.9% of women classified themselves as non-smokers. Women who live with a spouse or parents tend to under-report their smoking more than those who live alone or with others.
  
  
  CONCLUSIONS
  Since the number of self-reported female smokers was less than half of cotinine-verified smokers, current anti-smoking policies based on self-reported smoking prevalence rates in Korea should be further directed towards hidden female smokers. Also, biochemical verification needs to be considered with national tobacco surveys in Asian countries.
authors.affiliation: Department of Preventive Medicine, Ewha Womans University School of Medicine, Seoul, Korea.
authors.forename: Kyung-Hee
authors.initials: KH
authors.lastname: Jung-Choi
authors.forename: Young-Ho
authors.initials: YH
authors.lastname: Khang
authors.forename: Hong-Jun
authors.initials: HJ
authors.lastname: Cho
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003367:Cotinine / Q000652:urine*; D005260:Female; D006306:Health Surveys; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D056910:Republic of Korea / Q000453:epidemiology; D012650:Self Disclosure; D012737:Sex Factors; D012907:Smoking / Q000453:epidemiology* / Q000652:urine; D055815:Young Adult
chemical_list: D003367:Cotinine