1. Department of Medicine, Division of Hematology/Oncology, and Vanderbilt–Meharry Center of Excellence in Sickle Cell Disease, Vanderbilt University School of Medicine, Nashville, TN;
2. National Center on Birth Defects and Developmental Disabilities, Centers for Disease Control and Prevention, Atlanta, GA;
3. Rodeghier Consultants, Chicago, IL;
4. Massachusetts General Hospital and Harvard Medical School, Boston, MA;
5. Division of Allergy, Immunology, and Pulmonary Medicine, Department of Pediatrics, Washington University School of Medicine, St. Louis, MO; and
6. Department of Pediatrics and Medicine, Division of Hematology/Oncology, and Vanderbilt–Meharry Center of Excellence in Sickle Cell Disease, Vanderbilt University School of Medicine, Nashville, TN