1. Department of OtorhinolaryngologyMayo ClinicRochesterMinnesotaUSA
2. Alix School of MedicineMayo ClinicRochesterMinnesotaUSA
3. Division of BiostatisticsMayo ClinicRochesterMinnesotaUSA
4. Division of Pulmonary and Critical Care MedicineMayo ClinicRochesterMinnesotaUSA