1 Respiratory Medicine Unit and Oxford Respiratory National Institute for Health and Care Research Biomedical Research Centre, Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK. Electronic address: nayia.petousi@dpag.ox.ac.uk.
2 Respiratory Medicine Unit and Oxford Respiratory National Institute for Health and Care Research Biomedical Research Centre, Nuffield Department of Medicine, University of Oxford, John Radcliffe Hospital, Oxford OX3 9DU, UK.
3 Faculté de médecine et des sciences de la santé, Université de Sherbrooke, Sherbrooke, Québec, Canada.