1 Department of Surgery and MacClean Center of Bioethics, University of Chicago, Chicago, IL; Department of Defense Medical Ethics Center, Uniformed Services University of Health Sciences, Bethesda, MD.
2 Duke University Clinical Research Institute, Duke University, Durham, NC.
3 Department of Defense Medical Ethics Center, Uniformed Services University of Health Sciences, Bethesda, MD; Departments of Neurology and Biochemistry and Pellegrino Center for Clinical Bioethics, Georgetown University Medical Center, Washington DC.