1. Department of Clinical Neurosciences and Cambridge Centre for Parkinson‐plus University of Cambridge Cambridge UK
2. Cambridge University Hospitals NHS Foundation Trust Cambridge UK
3. Wessex Neurological Centre University Hospital Southampton Southampton UK
4. Norfolk and Norwich University Hospital Norwich UK
5. Division of Neuroscience and Experimental Psychology, Wolfson Molecular Imaging Centre University of Manchester Manchester UK
6. Departments of Geriatric Medicine and Nuclear Medicine University of Duisburg‐Essen Duisburg Germany
7. Oxford Parkinson's Disease Centre and Division of Neurology, Nuffield Department of Clinical Neurosciences University of Oxford Oxford UK
8. Department of Neuroscience Brighton and Sussex Medical School Brighton UK
9. Department of Neurology Royal Gwent Hospital Newport UK
10. Faculty of Medical Sciences Newcastle University Newcastle UK
11. Department of Clinical and Movement Neurosciences University College London, Queen Square Institute of Neurology London UK
12. MRC Cognition and Brain Sciences Unit University of Cambridge Cambridge UK