1. Department of Otolaryngology/Head and Neck Surgery; University of North Carolina at Chapel Hill; Chapel Hill North Carolina
2. Center for Innovations in Quality, Effectiveness and Safety, Michael E. DeBakey Veterans Affairs Medical Center; Houston Texas
3. Department of Medicine; Baylor College of Medicine; Houston Texas
4. Department of Head and Neck Surgery; The University of Texas MD Anderson Cancer Center; Houston Texas
5. Department of Epidemiology; The University of Texas MD Anderson Cancer Center; Houston Texas