1. Department of Otolaryngology, UT Southwestern Medical Center, Dallas, Texas, USA
2. American Academy of Otolaryngology–Head and Neck Surgery Foundation, Alexandria, Virginia, USA
3. Albany ENT & Allergy Services, PC, Albany, New York, USA
4. The Center for Pediatric Airway Disorders, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania, USA
5. Department of Otolaryngology, Washington University School of Medicine, St Louis, Missouri, USA
6. Department of Otolaryngology–Head and Neck Surgery, University of Iowa Hospitals & Clinics, Iowa City, Iowa, USA
7. Department of Emergency Medicine, Brigham and Women’s Hospital, Boston, Massachusetts, USA
8. University Hospitals Case Medical Center, Ear, Nose & Throat Institute, Cleveland, Ohio, USA
9. Pediatric Respiratory Care Department, Rainbow Babies & Children’s Hospital, Cleveland, Ohio, USA
10. Department of Otolaryngology, Massachusetts Eye and Ear Infirmary, Boston, Massachusetts, USA
11. Division of Laryngology, Department of Otolaryngology–Head and Neck Surgery, University of Washington School of Medicine, Seattle, Washington, USA