1. University of Texas Southwestern Medical Center, Dallas, Texas, USA
2. Oregon Health Sciences University, Portland, Oregon, USA
3. Eastern Virginia Medical School, Norfolk, Virginia, USA
4. Advanced ENT and Allergy, Louisville, Kentucky, USA
5. Johns Hopkins University School of Medicine, Baltimore, Maryland, USA
6. Intersect ENT, Palo Alto, California, USA
7. University of Minnesota School of Public Health, Minneapolis, Minnesota, USA