1. Moorfields Eye Hospital NHS Foundation Trust, London, UK
2. Imperial College Clinical Trials Unit, Imperial College London, London, UK
3. Centre for Health Economics and Medicines Evaluation, School of Medical and Health Sciences, Bangor University, Gwynedd, UK
4. Research Data and Statistics Unit (RDSU), Royal Marsden NHS Foundation Trust, London, UK
5. King’s Clinical Trial Unit, Research Management and Innovation Directorate, Institute of Psychiatry, Kings College, London, UK
6. Frimley Park Hospital, Camberley, UK