1. Neurology Service; Hospital Clínic de Barcelona, Universitat de Barcelona, IDIBAPS, Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED); Catalonia Spain
2. Department of Neurology; Innsbruck Medical University; Innsbruck Austria
3. Austrian PD Study Group
4. Department of Neurology and Karl Landsteiner Institute for Neuroimmunological and Neurodegenerative Disorders; Sozialmedizinisches Zentrum Ost; Vienna Austria
5. Department of Neurology; Wilhelminenspital; Vienna Austria
6. Unidad de Parkinson Teknon; Barcelona Spain
7. Department of Neurology; Medical University of Graz; Graz Austria
8. Neurology Service; Hospital Universitario Marqués de Valdecilla, University of Cantabria (UC); Santander Spain
9. Department of Neurology; Allgemeines Krankenhaus der Stadt Wien; Wien Vienna
10. Neurology Service; Hospital Universitario “12 de Octubre”, Universidad Complutense; Madrid Spain
11. Neurology Service; Department of Neuroscience; Hospital Germans Trias i Pujol; Badalona Spain
12. Movement Disorders Unit; Department of Neurology; Institut de Recerca Vall d'Hebron, Hospital Universitari Vall d'Hebron, Autonomous University of Barcelona; Barcelona Spain
13. Neurology Service; Hospital Mútua de Terrassa; Terrassa Spain