1 From the Dean's Office, Dell Medical School, University of Texas at Austin, Austin (S.C.J.); the Department of Neurology, University of California, San Francisco, San Francisco (J.D.E., M.F., A.S.K.); the Department of Emergency Medicine, University of Michigan, Ann Arbor (W.B.); the Division of Clinical Research, National Institute of Neurological Disorders and Stroke, Bethesda (R.A.C.), and Emmes, Rockville (A.S.L.) - both in Maryland; and the Data Coordination Unit, Department of Public Health Sciences, Medical University of South Carolina, Charleston (J.J.E., Y.Y.P.).