Accepted for Publication: April 22, 2011.
Author Contributions:Study concept and design: Stephan, Schüpbach, and Kaelin-Lang. Acquisition of data: Kipfer, Stephan, and Schüpbach. Analysis and interpretation of data: Kipfer, Schüpbach, Ballinari, and Kaelin-Lang. Drafting of the manuscript: Kipfer. Critical revision of the manuscript for important intellectual content: Stephan, Schüpbach, Ballinari, and Kaelin-Lang. Statistical analysis: Kipfer, Schüpbach, Ballinari, and Kaelin-Lang. Obtained funding: Kaelin-Lang. Administrative, technical, and material support: Kipfer and Stephan. Study supervision: Stephan, Schüpbach, and Kaelin-Lang.
Financial Disclosure: Dr Stephan received a fellowship from the Swiss National Science Foundation to perform scientific studies at the National Institutes of Health, Bethesda, Maryland. Dr Schüpbach received speaker's honoraria and travel reimbursement from Medtronic and UCB Pharma; he received research grants from Parkinson Switzerland and Mach-Gaensslen Stiftung Switzerland. Dr Kaelin-Lang received speaker's and advisory board honoraria and travel reimbursement from UCB Pharma, Boehringer Ingelheim, Novartis, and Allergan Inc; he received research grants from Parkinson Switzerland.
Funding/Support: This work was supported by a grant from Swiss Parkinson Association (Dr Kaelin-Lang).
Additional Contributions: Ethan Taub, MD, performed text editing.