1. Department of General Practice and Elderly Care Medicine, University Medical Center Groningen University of Groningen Groningen The Netherlands
2. Department of Pulmonary Diseases and Tuberculosis, University Medical Center Groningen University of Groningen Groningen The Netherlands
3. Department of Public Health, Faculty of Health Aarhus University Aarhus Denmark
4. The Danish National Rehabilitation Center for Neuromuscular Diseases Aarhus Denmark
5. Department of Health Psychology, University Medical Center Groningen University of Groningen Groningen The Netherlands
6. Department of Public and Occupational Health, Amsterdam Public Health Research Institute, Amsterdam UMC Vrije Universiteit Amsterdam Amsterdam The Netherlands