M. Pinsker and P. , Employment: Government employee. Volker Tronnier, MD, PhD: Medical Faculty of the Heidelberg University, Heidelberg; Employment: Government employee. Manja Kloss, MD: Medical Faculty of the Heidelberg University, Heidelberg; Employment: Government employee. Alfons Schnitzler, MD, PhD: Medical Faculty of the Heinrich Heine University, Dusseldorf; Advisory Boards: Pitie Salpetriere Volkswagen Foundation; Employment: Government employee, Jude MedicalANS, vol.Honoraria

K. Bötzel and P. Md, Employment: Government employee Adrian Danek, MD, PhD: Medical Faculty of the Ludwig-Maximillians-University, Munich; Employment: Government employee Grants: Cephalon (travel grants, Deutsche Parkinson Vereinigung (research funding); Employment: Government employee

A. Kupsch, M. , P. Allergan, . Desitin, . Gsk et al., German Ministry of Education and Research; Employment: Government employee MPsych: Medical Faculty of the Innsbruck Medical University, Innsbruck; Employment: Government employee. G. Deuschl, MD, PhD: Medical Faculty of the Christian-Albrechts University (CAU) German Research Council (Popgen) Kompetenznetz Parkinson; Honoraria: Lundbeck, Teva; Grants: German Research Council, German Ministry of Education and Research; Employment: Government employee; Royalties: Thieme publisher Medical Faculty of the Christian-Albrechts University (CAU), Kiel; Grants: German Research Council; Employment: Government em- ployee. Author Roles: C. Daniels: Research project: conception, organization, and execution; statistical analysis: design and execution; manuscript: writing of the first draft. P. Krack: Research project: conception, organization, and execution; statistical analysis: review and critique; manuscript: review and critique Research project: organization and execution; statistical analysis: review and critique, Elfriede Karner, pp.manu- REFERENCES

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