1 Office of Surveillance and Epidemiology, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Md. Electronic address: david.graham1@fda.hhs.gov.
2 Office of Biostatistics, Center for Drug Evaluation and Research, Food and Drug Administration, Silver Spring, Md.
3 Acumen LLC, Burlingame, Calif.
4 Centers for Medicare & Medicaid Services, Washington, DC.