Accepted for Publication: April 13, 2012.
Published Online: October 8, 2012. doi:10.1001/jamaneurol.2013.582
Author Contributions:Study concept and design: Prodoehl, Comella, Corcos, and Vaillancourt. Acquisition of data: Prodoehl, Planetta, and Vaillancourt. Analysis and interpretation of data: Prodoehl, Planetta, Kurani, and Vaillancourt. Drafting of the manuscript: Prodoehl, Corcos, and Vaillancourt. Critical revision of the manuscript for important intellectual content: Prodoehl, Planetta, Kurani, Comella, and Vaillancourt. Statistical analysis: Prodoehl, Planetta, Kurani, and Vaillancourt. Obtained funding: Corcos and Vaillancourt. Administrative, technical, and material support: Prodoehl and Vaillancourt. Study supervision: Vaillancourt.
Conflict of Interest Disclosures: Dr Comella has served as a consultant for Allergan, Merz, Ipsen, Esai, and Boehringer; has received royalties from Kluwer Publishing and Cambridge University Press; and has received research grants that go to her institution from Boehringer, Ipsen, Merz, and the National Institutes of Health, and her institution has also received support from a Parkinson Research Center grant from the Parkinson's Disease Foundation. Drs Vaillancourt and Corcos have received funding from the National Institutes of Health (grants R01-NS-52318, R01-NS-58487, R01-NS-40902, and R01-NS-28127) and the Michael J. Fox Foundation for Parkinson Research.
Funding/Support: This work was supported by the National Institutes of Health (grants R01-NS-52318, R01-NS-58487, R01-NS-40902, and R01-NS-28127), the Michael J. Fox Foundation for Parkinson Research, and a Parkinson Research Center grant from the Parkinson's Disease Foundation.
Additional Contributions: We thank the staff at the Section for Movement Disorders in the Department of Neurological Sciences at Rush University Medical Center, Chicago, Illinois, and the patients for their time and commitment to this research.