aInstitute of Cancer Epidemiology, Danish Cancer Society
bNational Institute of Occupational Health, Copenhagen
cDepartment of Clinical Epidemiology, Aarhus University Hospital, Aarhus
dDepartment of Clinical Epidemiology, Aarhus University Hospital, Aalborg
eInstitute for Science, Systems and Models, University of Roskilde, Roskilde, Denmark
fInternational Epidemiology Institute, Rockville, MD, USA
gDepartment of Medicine, Vanderbilt University Medical Center, Vanderbilt-Ingram Cancer Center, Nashville, TN, USA
Correspondence to Søren Friis, Institute of Cancer Epidemiology, Danish Cancer Society, Strandboulevarden 49, DK-2100 Copenhagen, Denmark
Tel: +45 35 25 76 24; fax: +45 35 25 77 31, +45 35 25 77 34; e-mail: [email protected]
Received 25 January 2007 Accepted 7 April 2007