1. Medical School of Federal University of Health Sciences of Porto AlegrePorto AlegreBrazil
2. Graduate Program in Pediatrics of Federal University of Health Sciences of Porto AlegrePorto AlegreBrazil
3. Otorhinolaryngology Service of Santa Casa de Misericórdia Hospital of Porto AlegrePorto AlegreBrazil
4. Pediatric Otolaryngology Service of Santo Antonio Children’s Hospital of Porto AlegrePorto AlegreBrazil
5. Medical School of Federal University of Rio Grande do SulPorto AlegreBrazil
6. Department of Otolaryngology–Head and Neck SurgeryVanderbilt University Medical CenterNashvilleTennesseeUSA