• Jørn Olsen
  • Kaare Christensen
  • Jeff Murray
  • Anders Ekbom
Part of the Springer Series on Epidemiology and Public Health book series (SSEH, volume 1)


A confounder is an exposure, external to our hypothesis, that biases our measure of association unless it is controlled. When we compare our exposed population with the unexposed comparison group the disease outcome will be different in the two groups even if the exposed had not been exposed. The comparison is confounded by an external factor that has to be a cause of the disease or a strong correlate for a cause of the disease.


Smoking Prevalence Lung Cancer Risk Dietary Component Exposed Population Hand Eczema 
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Copyright information

© Springer Science+Business Media, LLC 2010

Authors and Affiliations

  • Jørn Olsen
    • 1
  • Kaare Christensen
    • 2
  • Jeff Murray
    • 3
  • Anders Ekbom
    • 4
  1. 1.School of Public HealthUniversity of California, Los AngelesLos AngelesUSA
  2. 2.Institute of Public HealthUniversity of Southern DenmarkOdense CDenmark
  3. 3.Department of Pediatrics, 2182 MedLabsUniversity of IowaIowa CityUSA
  4. 4.Department of MedicineKarolinska InstitutetStockholmSweden

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