[1] Duke Univ, Med Ctr, Ctr Clin Hlth Policy Res, Duke Ctr Cerebrovasc Dis, Durham, NC 27710 USA
[2] Duke Univ, Ctr Clin Hlth Policy Res, Dept Med Neurol, Durham, NC 27710 USA
[3] Duke Univ, Ctr Clin Hlth Policy Res, Stroke Policy Program, Durham, NC 27710 USA
[4] Durham VA Med Ctr, Durham, NC USA