1. From the Department of Biostatistics and Epidemiology, College of Public Health (J.A.R., J.D.P., D.R.T., S.K.V., J.N.G.), the Hematology–Oncology Section, Department of Medicine, College of Medicine (J.A.R., J.N.G.), and the Maternal–Fetal Medicine Section, Department of Obstetrics and Gynecology, College of Medicine (D.R.D., J.J.M., E.J.K.), University of Oklahoma Health Sciences Center, Oklahoma City.