1. Department of Public Health and Nursing, Norwegian University of Science and Technology, 7034 Trondheim, Norway
2. Department of Internal Medicine, Levanger Hospital, Health Trust Nord-Trøndelag, 7600 Levanger, Norway
3. Department of Health Register, The Norwegian Directorate of Health, 0213 Trondheim, Norway
4. Department of Cardiology, Oslo University Hospital, Rikshospitalet, 0372 Oslo, Norway
5. Department of Epidemiology and Biostatistics, School of Public Health, Imperial College London, St. Mary’s Campus, Norfolk Place, Paddington, London W2 1PG, UK
6. Department of Nutrition, Oslo New University College, 0456 Oslo, Norway
7. Department of Endocrinology, Morbid Obesity and Preventive Medicine, Oslo University Hospital, 0372 Oslo, Norway
8. Department of Obstetrics and Gynecology, Levanger Hospital, Nord-Trøndelag Hospital Trust, 7600 Levanger, Norway
9. Department of Medicine, Beth Israel Deaconess Medical Center, Boston, MA 02215, USA
10. Department of Global Public Health, Karolinska Institutet, 17 176 Stockholm, Sweden
11. Regional Center for Health Care Improvement, St. Olav’s University Hospital, 7030 Trondheim, Norway