1. Department of Emergency Medicine The University of Texas M. D. Anderson Cancer Center Houston Texas USA
2. College of Medicine University of the Philippines Manila Manila Philippines
3. Baylor College of Medicine Houston Texas USA
4. Department of Epidemiology The University of Texas M. D. Anderson Cancer Center Houston Texas USA
5. Department of Biostatistics The University of Texas M. D. Anderson Cancer Center Houston Texas USA
6. Department of Head and Neck Surgery The University of Texas M. D. Anderson Cancer Center Houston Texas USA