Lung cancer and passive smoking: association of an artefact due to misclassification of smoking habits?

Toxicol Lett. 1987 Jan;35(1):157-62. doi: 10.1016/0378-4274(87)90102-0.


1775 subjects were asked about their current use of tobacco products or nicotine chewing gum. 1537 provided a sample of saliva for cotinine analysis. Of 808 who claimed not to be users of such products, 20 (2.5%) had cotinine values above 30 ng/ml, suggesting their self-reports were false. In another study, 540 subjects were interviewed on two occasions. 10% of subjects claiming on one occasion never to have smoked made inconsistent statements on the other occasion. A third study showed a strong tendency for smokers to marry smokers. Bias caused by misclassification of smoking habits coupled with between-spouse smoking habit concordance can completely explain reported apparent excesses in lung cancer risk in non-smokers married to smokers.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Chewing Gum
  • Cotinine / analysis
  • Female
  • Humans
  • Interviews as Topic / standards
  • Lung Neoplasms / etiology*
  • Male
  • Marriage
  • Research
  • Research Design
  • Risk
  • Saliva / analysis
  • Tobacco Smoke Pollution / adverse effects*


  • Chewing Gum
  • Tobacco Smoke Pollution
  • Cotinine