1 Respiratory Epidemiology, Occupational Medicine and Public Health, National Heart and Lung Institute, Imperial College, London, UK a.amaral@imperial.ac.uk.
2 Respiratory Epidemiology, Occupational Medicine and Public Health, National Heart and Lung Institute, Imperial College, London, UK.
3 University of British Columbia Heart Lung Innovation Center, Vancouver, BC, Canada.
4 Dept of Pulmonary Medicine, Paracelsus Medical University, Salzburg, Austria.
5 Dept of Medical Sciences: Respiratory Medicine and Allergology, Uppsala University, Uppsala, Sweden.
6 Faculty of Medicine, University of Iceland and Landspitali University Hospital, Reykjavik, Iceland.
7 Division of Pulmonary Critical Care and Sleep Medicine, University of Kentucky, Lexington, KY, USA.
8 Dept of Medicine, University of Cape Town, Cape Town, South Africa.
9 Oregon Health and Sciences University, Portland, OR, USA.