1. Department of Respiratory Medicine, Homerton University Hospital, London, Department of Respiratory Medicine
2. Department of Respiratory Medicine, School of Basic & Medical Biosciences, King's College London, London
3. Department of Respiratory Medicine, Whipps Cross University Hospital, London
4. Blizard Institute, Barts and the London School of Medicine and Dentistry
5. Department of Respiratory Medicine, Queen Mary University of London, London, UK
6. Departamento de Eletrónica, Telecomunicações e Informática, Institute of Electronics and Informatics Engineering, University of Aveiro, Aveiro, Portugal
7. Department of Respiratory Medicine, Homerton University Hospital, London