1. Department of Otorhinolaryngology–Head & Neck Surgery University of Pennsylvania Philadelphia Pennsylvania USA
2. Department of Medicine University of Pennsylvania Philadelphia Pennsylvania USA
3. Perelman School of Medicine, University of Pennsylvania Philadelphia Pennsylvania USA
4. Department of Radiation Oncology University of Pennsylvania Philadelphia Pennsylvania USA
5. Department of Paediatrics University of Texas Health Science Centre at San Antonio San Antonio Texas USA
6. Leonard Davis Institute of Health Economics University of Pennsylvania Philadelphia Pennsylvania USA