1. Department of NeurologyAmsterdam UMC, University of Amsterdam Amsterdam The Netherlands
2. Department of PsychologyUniversity of Amsterdam Amsterdam The Netherlands
3. Department of Medical Psychology, Academic Medical Center AmsterdamAmsterdam UMC, University of Amsterdam Amsterdam The Netherlands
4. Department of Clinical Epidemiology, Biostatistics and BioinformaticsAmsterdam UMC, University of Amsterdam Amsterdam The Netherlands
5. Nuffield Department of MedicineUniversity of Oxford Oxford United Kingdom
6. Oxford University Clinical Research Unit, Wellcome Trust Major Overseas Programme Ho Chi Minh City Vietnam
7. New Zealand Brain Research InstituteBrain Research New Zealand ‐ Rangahau Roro Aotearoa Christchurch New Zealand
8. Morton and Gloria Shulman Movement Disorders Centre and the Edmond J Safra Program in Parkinson's DiseaseToronto Western Hospital, University of Toronto Ontario Canada
9. Arizona Parkinson's Disease ConsortiumMayo Clinic Arizona, Scottsdale, Arizona, USA, and Banner Sun Health Research Institute Sun City Arizona USA
10. Departments of Psychiatry and NeurologyUniversity of Pennsylvania School of Medicine, and Parkinson's Disease and Mental Illness Research, Philadelphia Veterans Affairs Medical Center Philadelphia Pennsylvania USA
11. Department of Medicine, Faculty of MedicineIDIBAPS, University of Barcelona Barcelona Spain
12. The Norwegian Centre for Movement Disorders, Department of Neurologyand Memory Clinic, Stavanger University Hospital Stavanger Norway
13. Department of Neurosurgery and Institute of NeuropathologyParacelsus‐Elena‐Klinik, Kassel, Germany, and University Medical Center Goettingen Goettingen Germany
14. Department of Neurological Sciences, Section of Parkinson Disease and Movement DisordersRush University Medical Center Chicago Illinois USA
15. Department of Clinical Neuropsychology and Center for NeuromodulationBarrow Neurological Institute Phoenix Arizona USA
16. Institute of Neuroscience, Newcastle University Upon Tyne, Newcastle UK
17. Department of Neurosciences University of California San DiegoParkinson and Other Movement Disorder Center San Diego, California USA