1. Department of Otorhinolaryngology-Head and Neck Surgery, University of Pennsylvania; Perelman School of Medicine; Philadelphia PA
2. Sidney Kimmel Medical College; Thomas Jefferson University; Philadelphia PA
3. Perelman School of Medicine; University of Pennsylvania; Philadelphia PA
4. Leonard Davis Institute of Health Economics; University of Pennsylvania; Philadelphia PA
5. Department of Biostatistics and Epidemiology, University of Pennsylvania; Perelman School of Medicine; Philadelphia PA