1. Portsmouth Hospitals NHS Trust, Portsmouth, UK
2. St George’s University Hospitals NHS Foundation Trust, London, UK
3. Medical School, University College London, London, UK
4. University College London Hospitals NHS Foundation Trust, London, UK
5. St Pancras Clinical Research, London, UK
6. Consultant Royal National ENT and Eastman Dental Hospitals and Pain Management Centre, National Hospital for Neurology and Neurosurgery, UCLH NHS Foundation Trust, London, UK