1. Department of Pediatrics, Vanderbilt-Meharry Center of Excellence in Sickle Cell Disease, Nashville, TN;
2. Rodeghier Consulting, Chicago, IL;
3. Department of Biostatistics, University of North Carolina, Chapel Hill, NC;
4. Division of Hematology, Department of Medicine, Johns Hopkins University School of Medicine, Baltimore, MD;
5. Division of Hematology and Oncology, Department of Medicine, Vanderbilt University Medical Center, Nashville, TN; and
6. Center for Sickle Cell Disease, University of Tennessee Health Science Center, Memphis, TN