[1] Natl Inst Hlth, Fogarty Int Ctr, Int Cerebrovasc Translat Clin Res Training Progra, Stroke Serv, Karachi, Pakistan
[2] Aga Khan Univ, Karachi, Pakistan
[3] Natl Inst Hlth, Fogarty Int Ctr, Int Cerebrovasc Translat Clin Res Training Progra, Karachi, Pakistan
[4] Aga Khan Univ, Epidemiol & Biostat Program, Karachi, Pakistan
[5] Aga Khan Univ, Dept Community Hlth Sci, Karachi, Pakistan
[6] Dow Univ Hlth Sci, Karachi, Pakistan
[7] Dow Univ Hlth Sci, Dow Inst Radiol, Karachi, Pakistan
[8] Aga Khan Univ, Dept Med, Karachi, Pakistan
[9] Univ Penn, Comprehens Stroke Ctr, Div Stroke & Neurointens Care, Philadelphia, PA 19104 USA