1. Department of Neurology; University of California; San Francisco and Parkinson's Disease Research; Education, and Clinical Center, San Francisco Veterans Affairs Medical Center; San Francisco CA
2. Cooperative Studies Program, Department of Veterans Affairs Office of Research and Development; Washington DC
3. Domenic Reda and Kimberly Carlson Hines VA Cooperative Studies Program Coordinating Center; Hines; IL USA
4. Department of Neurological Surgery; University of California; San Francisco San Francisco CA
5. Department of Neurosurgery; University of Nebraska Medical Center; Omaha NE
6. Center of Innovation for Complex Chronic Healthcare, Edward J. Hines, Jr. VA Hospital, Hines, IL, USA Stritch School of Medicine; Loyola University; Maywood IL, USA
7. Department of Neurology; University of Pennsylvania School of Medicine; Philadelphia PA