C Horst1, M E J Callister2, S M Janes3. 1. Lungs for Living, UCL Respiratory, University College London, London, UK. Electronic address: carolyn.horst@ucl.ac.uk. 2. Department of Respiratory Medicine, Leeds Teaching Hospitals NHS Trust, St James's University Hospital, Leeds, UK. 3. Lungs for Living, UCL Respiratory, University College London, London, UK.