1. Respiratory Care Department, Prince Sultan Military College of Health Sciences, Damman, Kingdom of Saudi Arabia;
2. Respiratory Care Department, Prince Sultan Military Medical City, Riyadh, Saudi Arabia;
3. The University Sleep Disorders Center, Department of Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia;
4. Department of Family and Community Medicine, College of Medicine, King Saud University, Riyadh, Saudi Arabia