[1] Univ Alabama Birmingham, Dept Neurol, 1813 6th Ave South,RWUH M226, Birmingham, AL 35294 USA
[2] Birmingham Vet Affairs Med Ctr, Stroke Program, Birmingham, AL USA
[3] Univ Texas Houston, Mem Hermann Med Ctr, Dept Neurol, Houston, TX USA
[4] Univ Penn, Dept Neurol, Philadelphia, PA 19104 USA
[5] Univ Alabama Birmingham, Dept Epidemiol, Birmingham, AL 35294 USA
[6] Univ Alabama Birmingham, Hlth Serv & Outcomes Res Ctr Outcome & Effectiven, Birmingham, AL 35294 USA
[7] Univ Alabama Birmingham, Ctr Excellence Comparat Effectiveness Res Elimina, Minor Hlth & Hlth Dispar Res Ctr MHRC, Birmingham, AL 35294 USA
[8] Birmingham Vet Affairs Med Ctr, GRECC, Birmingham, AL USA
[9] Duke Univ, Sch Med, Durham, NC USA
[10] Columbia Univ, Dept Neurol, Gertrude Sergievsky Ctr, New York, NY USA
[11] Univ Penn, Dept Clin Epidemiol & Biostat, Philadelphia, PA 19104 USA
[12] Univ Penn, Dept Emergency Med, Philadelphia, PA 19104 USA