1. National Center for Rehabilitative Auditory Research (NCRAR) VA Portland Healthcare System Portland Oregon USA
2. Department of Otolaryngology Oregon Health & Science University Portland Oregon USA
3. Department of Medical Informatics and Clinical Epidemiology Oregon Health & Science University Portland Oregon USA
4. Department of Neurology Oregon Health & Science University Portland Oregon USA
5. San Francisco VA Health Care System San Francisco California USA
6. Department of Neurology University of California San Francisco California USA
7. Pulmonary Section and Sleep Medicine VA Pittsburgh Healthcare System Pittsburgh Pennsylvania USA
8. Division of Pulmonary Allergy Critical Care Medicine UPMC and University of Pittsburgh Pittsburgh Pennsylvania USA
9. Department of Medicine University of California San Francisco California USA