1. Neonatology Association Limited, Obstetrix Medical Group of Phoenix, Mednax, Phoenix, Arizona
2. Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Los Angeles County+USC Medical Center, Keck School of Medicine, University of Southern California, Los Angeles
3. Department of Preventive Medicine, Keck School of Medicine, University of Southern California, Los Angeles
4. Fetal and Neonatal Institute, Division of Neonatology, Children’s Hospital Los Angeles, Department of Pediatrics, Keck School of Medicine, University of Southern California, Los Angeles
5. Schaeffer Center for Health Policy and Economics, University of Southern California, Los Angeles