[1] Prince Sultan Mil Coll Hlth Sci, Dept Resp Care, Dammam 34313, Saudi Arabia
[2] Univ Bolton, Sch Arts & Creat Technol, Bolton BL3 5AB, England
[3] Univ Sheffield, Informat Sch, Sheffield S10 2SJ, England
[4] Jazan Univ, Fac Appl Med Sci, Resp Therapy Dept, Jazan 45142, Saudi Arabia
[5] Umm Al Qura Univ, Coll Appl Med Sci, Resp Care Program, Mecca 24382, Saudi Arabia
[6] King Abdulaziz Univ, Fac Med Rehabil Sci, Resp Therapy Dept, Jeddah 21589, Saudi Arabia
[7] King Faisal Univ, Resp Therapy Dept, Al Hasa 31982, Saudi Arabia
[8] Umm Al Qura Univ, Fac Med, Mecca 21514, Saudi Arabia
[9] UCL, Div Med, London, England