[1] Flinders Univ S Australia, Adelaide Inst Sleep Hlth, Daw Pk, SA, Australia
[2] Flinders Univ S Australia, Adelaide Inst Sleep Hlth, Thomas Motor Neurone Res Project, Daw Pk, SA, Australia
[3] Flinders Med Ctr, Dept Resp Med, Bedford Pk, SA, Australia
[4] Repatriat Gen Hosp, Dept Speech Pathol, Daw Pk, SA, Australia