title: Selection bias due to non-response in a health survey among patients with rheumatoid arthritis.
abstract: BACKGROUND
  Non-response may lead to bias in health(care) outcomes.
  
  
  METHODS
  We compared respondents (n = 334) to a questionnaire survey among patients with rheumatoid arthritis with non-respondents (n = 68) and determined predictors of (non-)response. The bias in prevalence estimates of health characteristics and health care use was quantified.
  
  
  RESULTS
  Self-reported pain and health care utilization were the most important predictors of (non-)response with respondents experiencing pain more often and more often using specific health care services. Bias concerned especially an underestimation of 'never having pain' (60%) and 'no contact with health care services' (51%).
  
  
  CONCLUSIONS
  More insight into the phenomenon of non-response is important to assess disease burden and health care burden more precisely.
authors.affiliation: Department of Social Medicine, Academic Medical Centre, University of Amsterdam, The Netherlands. i.rupp@amc.uva.nl
authors.forename: Ines
authors.initials: I
authors.lastname: Rupp
authors.forename: Mattanja
authors.initials: M
authors.lastname: Triemstra
authors.forename: Hendriek C
authors.initials: HC
authors.lastname: Boshuizen
authors.forename: Catharina E
authors.initials: CE
authors.lastname: Jacobi
authors.forename: Huibert J
authors.initials: HJ
authors.lastname: Dinant
authors.forename: Geertrudis A M
authors.initials: GA
authors.lastname: van den Bos
mesh_terms: D001172:Arthritis, Rheumatoid / Q000453:epidemiology*; D016009:Chi-Square Distribution; D005260:Female; D006304:Health Status; D006306:Health Surveys; D006801:Humans; D016015:Logistic Models; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D015995:Prevalence; D015983:Selection Bias