title: Non-response bias in a lifestyle survey.
abstract: BACKGROUND
  Monitoring health targets is often undertaken using questionnaire surveys of lifestyle risk factors. Non-response bias is recognized but rarely quantified.
  
  
  METHODS
  Following a questionnaire survey on a random sample of 6009 residents of Somerset with a response rate of 57.6 per cent, a telephone survey was undertaken on a random sample of 400 non-responders. A small number of the more important questions from the questionnaire were put to the non-responders over the phone.
  
  
  RESULTS
  Fifty-nine per cent of the sample were contacted and agreed to participate. Statistically significant differences between responders and non-responders to the original questionnaire were detected for current smoking, hazardous alcohol consumption and lack of moderate or vigorous activity.
  
  
  CONCLUSIONS
  Lifestyle questionnaire surveys need to include an assessment of the non-response bias.
authors.affiliation: South Humber Health Authority, North Lincolnshire.
authors.forename: A
authors.initials: A
authors.lastname: Hill
authors.forename: J
authors.initials: J
authors.lastname: Roberts
authors.forename: P
authors.initials: P
authors.lastname: Ewings
authors.forename: D
authors.initials: D
authors.lastname: Gunnell
mesh_terms: D000293:Adolescent; D000328:Adult; D015982:Bias; D004739:England; D005260:Female; D006306:Health Surveys; D006801:Humans; D008019:Life Style; D008297:Male; D008875:Middle Aged; D010352:Patient Dropouts / Q000706:statistics & numerical data*; D015995:Prevalence; D015203:Reproducibility of Results; D011795:Surveys and Questionnaires / Q000592:standards*; D013689:Telephone