1. Department of Respiratory Medicine, Repatriation General Hospital, Daw Park, Australia
2. School of Medicine, Flinders University, Adelaide, Australia
3. Respiratory Epidemiology and Clinical Research Unit, Montreal Chest Institute of the Royal Victoria Hospital, McGill University Health Center, Quebec, Canada
4. Department of Medical Psychology and Department of Pulmonary Diseases, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
5. Section of Allergy and Immunology, University of Pennsylvania, PA, USA
6. Department of Medicine, The University of Texas Health Science Center at Tyler, TX, USA
7. College of Nursing, University of Colorado Denver, CO, USA
8. Department of Pulmonary Medicine, Medisch Spectrum Twente, KA Enschede, The Netherlands
9. Imperial College London, NHLI Division, South Kensington Campus, London, UK
10. Department of Research Methodology, Measurement and Data Analysis, University of Twente, AE Enschede, The Netherlands