1. General Practice Research Unit; Department of Public Health and General Practice; Norwegian University of Science and Technology; Trondheim Norway
2. Department of Community Medicine; The Arctic University Tromsø; Tromsø Norway
3. Faculty of Social Science and History; Volda University College; Volda Norway
4. Department of Community Medicine; University of Bergen; Bergen Norway
5. Department of Microbiology; Haukeland University Hospital; Bergen Norway
6. Department of Clinical Science; University of Bergen; Bergen Norway
7. Department of Philosophy; University of Oslo; Oslo Norway