1. HUNT Research Centre, Department of Public Health and Nursing, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Levanger, Norway
2. Department of Endocrinology, St. Olavs Hospital, Trondheim University Hospital, Trondheim, Norway
3. Hormone Laboratory, Department of Medical Biochemistry, Oslo University Hospital, Oslo, Norway
4. Department of Clinical and Molecular Medicine, Faculty of Medicine and Health Sciences, Norwegian University of Science and Technology, Trondheim, Norway