1. Department of Respiratory Medicine, University Hospital Gasthuisberg, Leuven, Belgium
2. Department of Pulmonary Medicine, Cliniques universitaires St Luc, and Institute of Experimental and Clinical Research, Université Catholique de Louvain, Brussels, Belgium
3. Department of Pulmonary Medicine, CHU Sart-Tilman, Liege, I3GIGA Research Group, University of Liege, Liege, Belgium
4. Department of Respiratory Medicine, Ghent University Hospital, Gent, Belgium