1. Department of Otolaryngology-Head and Neck Surgery; Stanford University; Stanford California
2. Division of Pediatric Otolaryngology-Head and Neck Surgery; Cincinnati Children's Hospital Medical Center; Cincinnati Ohio
3. Department of Otolaryngology-Head and Neck Surgery; University of Cincinnati College of Medicine; Cincinnati Ohio
4. Division of Biostatistics and Epidemiology; Cincinnati Children's Hospital Medical Center; Cincinnati Ohio
5. Division of Cardiothoracic Surgery; Cincinnati Children's Hospital Medical Center; Cincinnati Ohio
6. Division of Cardiothoracic Surgery, Section of Pediatric Cardiothoracic Surgery; Washington University School of Medicine/St. Louis Children's Hospital; St. Louis Missouri
7. Department of Otorhinolaryngology; Mayo Clinic College of Medicine; Rochester Minnesota
8. Department of Otorhinolaryngology-Head and Neck Surgery; Montefiore Medical Center; Bronx New York U.S.A.