1. Faculty of Health Studies , VID Specialized University , Box 184 Vinderen , NO-0319 Oslo , Norway , Phone: +4799090005
2. Department of Health Sciences, Institute of Health and Society , University of Oslo , Oslo , Norway
3. Oslo Centre for Biostatistics and Epidemiology , Oslo University Hospital and University of Oslo , Oslo , Norway
4. Norwegian National Advisory Unit on CFS/ME, Division of Pediatrics, Rikshospitalet , Oslo University Hospital , Oslo , Norway
5. CFS/ME Center, Division of Medicine, Department of Geriatrics Aker , Oslo University Hospital , Aker, Oslo , Norway
6. Centre for Shared Decision Making and Collaborative Care Research, Division of Medicine , Oslo University Hospital , Oslo , Norway
7. Department of Psychiatry & Psychology , College of Medicine and Science, Mayo Clinic , Rochester, MN , USA
8. Institute of Clinical Medicine, Faculty of Medicine , University of Oslo , Oslo , Norway