1. Surgical and Interventional Trials Unit, University College London , London, UK
2. South London Healthcare NHS Trust , London, UK
3. Nightingale-Saunders Clinical Trials & Epidemiology Unit, King's Clinical Trials Unit, Kings College London , London, UK
4. Royal Free London NHS Foundation Trust , London, UK
5. Research Department of Primary Care and Population Health, University College , London, UK
6. Thoracic Surgery Clinic, Institute for Lung Diseases of Vojvodina , Sremska Kamenica, Serbia
7. Centre for Trials Research, Cardiff University , Cardiff, UK
8. Clinical Operational Research Unit, University College London , London, UK