1. Research Unit of General Practice, Institute of Public Health, University of Southern Denmark, J. B. Winsløws Vej 9A, 5000 Odense C, Denmark
2. The Research Unit for General Practice, Danish Research Centre for Cancer Diagnosis in Primary Care (CaP), Department of Public Health, Aarhus University, Bartholins Allé 2, 8000 Aarhus C, Denmark