[1] Austin & Repatriat Med Ctr, Natl Stroke Res Inst, W Heidelberg, Vic 3081, Australia
[2] Austin & Repatriat Med Ctr, Dept Neurol, W Heidelberg, Vic 3081, Australia
[3] Alfred Hosp, Monash Med Sch, Dept Epidemiol & Prevent Med, Prahran, Vic 3181, Australia
[4] Univ Melbourne, Dept Med, Parkville, Vic 3052, Australia