1. Otolaryngology-Head and Neck Surgery, Tripler Army Medical Center, HI 96859, USA
2. Stanford Hospital and Clinics, Department of Psychiatry and Behavioral Sciences, Division of Sleep Medicine, Stanford, CA 94063, USA
3. Department of Head and Neck Surgery, David Geffen School of Medicine at UCLA, Los Angeles, CA 90095, USA
4. Department of Otolaryngology-Head and Neck Surgery, Division of Sleep Surgery and Medicine, Stanford, CA 94063, USA
5. Wright State University Boonshoft School of Medicine, Dayton, OH 45435, USA
6. Department of Otorhinolaryngology, Sleep Medicine Centre, Hospital CUF Porto, 4100-180 Porto, Portugal
7. Center for Research in Health Technologies and Information Systems (CINTESIS), University of Porto, 4200-450 Porto, Portugal