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Web-based survey attracted age-biased sample with more severe illness than paper-based survey

Atle Klovning1, Hogne Sandvik, Steinar Hunskaar

  • 1Section for General Practice, Department of Public Health and Primary Health Care, University of Bergen, Kalfarveien, Bergen, Norway. atle.klovning@medisin.uio.no

Journal of Clinical Epidemiology
|February 28, 2009
PubMed
Abstract

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