title: Japanese spousal smoking study revisited: how a tobacco industry funded paper reached erroneous conclusions.
abstract: OBJECTIVE
  To provide a participant's account of the development of a paper commissioned by the tobacco industry examining the reliability of self reported smoking status; to redress the distorted report of this Japanese spousal smoking study which evaluated the reliability and validity of self reported smoking status, and estimated confounding by diet and lifestyle factors.
  
  
  METHODS
  Repeated interviews on smoking status and its verification by environmental and biological markers for environmental tobacco smoke (ETS) exposure.
  
  
  METHODS
  Urban wives in Osaka City and Sizuoka City, Japan
  
  
  METHODS
  Semi-random sampling of 200 wives in each city. From the Osaka subjects, 100 non-smoking wives were selected for the validity study.
  
  
  METHODS
  Kappa coefficient for reliability of self reported smoking status. Correlation coefficients between environmental nicotine concentration, cotinine in saliva and urine, and self reported smoking status.
  
  
  RESULTS
  The kappa coefficient for the repeated interview was high suggesting sufficient reliability of the response. The proportion of self reported current smokers misclassified as non-smokers was equivalent to the misclassified self reported non-smokers. Ambient concentration of nicotine and personal exposure to nicotine correlated with each other and also with salivary cotinine and self reported ETS exposure but not with urinary cotinine/creatinine ratio (CCR). There was no major difference in diet and lifestyle related to husband's smoking status.
  
  
  CONCLUSIONS
  Self reported smoking status by Japanese wives shows high reliability. It also shows high validity when verified by both nicotine exposure and salivary cotinine, but not by CCR. A previous report questioning the credibility of self reported smoking status, based on questionable CCR, could thus be of dubious validity. In addition, possible dietary and lifestyle confounding factors associated with smoking husbands were not demonstrable, a finding not reported previously. Using all the data from this project changes the conclusion of the previous published report. In addition to the distortion of scientific findings by a tobacco industry affiliated researcher, anti-smoking campaigners made attempts to intimidate and suppress scientific activities. These distortions of science should be counteracted.
authors.affiliation: Department of Hygiene and Public Health, Teikyo University School of Medicine, 2-11-1, Kaga, Tokyo 173-8605, Japan. eyano@med.teikyo-u.ac.jp
authors.forename: E
authors.initials: E
authors.lastname: Yano
mesh_terms: D000328:Adult; D016265:Conflict of Interest; D015986:Confounding Factors, Epidemiologic; D003367:Cotinine / Q000032:analysis / Q000652:urine; D003404:Creatinine / Q000652:urine; D004032:Diet; D005260:Female; D006801:Humans; D007564:Japan; D008019:Life Style; D008175:Lung Neoplasms / Q000209:etiology; D008875:Middle Aged; D009538:Nicotine / Q000032:analysis; D015203:Reproducibility of Results; D012107:Research Design; D012109:Research Support as Topic; D012463:Saliva / Q000737:chemistry; D012650:Self Disclosure; D012907:Smoking / Q000378:metabolism; D018454:Spouses / Q000523:psychology; D019460:Tobacco Industry; D014028:Tobacco Smoke Pollution / Q000009:adverse effects / Q000032:analysis*
chemical_list: D014028:Tobacco Smoke Pollution; D009538:Nicotine; D003404:Creatinine; D003367:Cotinine