1. Department of Public Health, Faculty of Health, Aarhus University, Aarhus, Denmark
2. DEFACTUM, Aarhus, Denmark
3. Spine Centre of Southern Denmark, Hospital Lillebaelt, Middelfart, Denmark
4. Department of Regional Health Research, University of Southern Denmark, Odense, Denmark
5. Regional Hospital West Jutland, Herning, Denmark
6. Department of Public Health, Research Unit of User Perspectives, University of Southern Denmark, Odense, Denmark
7. SANO Aarhus, Aarhus, Denmark