1. Division of Neonatology, Department of Pediatrics, University of Utah, Salt Lake City, Utah
2. Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, University of Utah, Salt Lake City, Utah
3. Division of Epidemiology, Department of Internal Medicine, University of Utah, Salt Lake City, Utah
4. San Diego Neonatology, Department of Pediatrics, Sharp Mary Birch Hospital for Women and Newborn, San Diego, California
5. Division of Neonatology, Department of Pediatrics, University of California at San Diego, San Diego, California
6. Division of Neonatology, Department of Pediatrics, Loma Linda University School of Medicine, Loma Linda, California