1. Division of Pediatric Otolaryngology, Head and Neck Surgery Cincinnati Children's Hospital Medical Center Cincinnati Ohio U.S.A.
2. Department of Otolaryngology Head & Neck Surgery University of Cincinnati College of Medicine Cincinnati Ohio U.S.A.
3. Department of Otolaryngology, Head and Neck Surgery University of Minnesota Minneapolis Minnesota U.S.A.
4. Department of Otolaryngology, Head and Neck Surgery Ohio State University Columbus Ohio U.S.A.
5. Division of Biostatistics and Epidemiology Cincinnati Children's Hospital Medical Center Cincinnati Ohio U.S.A.
6. Department of Otolaryngology, Head and Neck Surgery University of Cincinnati Cincinnati Ohio U.S.A.