1. Department of Epidemiology, Emory University Rollins School of Public Health, Atlanta, Georgia
2. Division of Neonatal and Developmental Medicine, Department of Pediatrics, Stanford University School of Medicine, Stanford, California
3. Division of Cardiology, Department of Pediatrics, Stanford University School of Medicine, Stanford, California
4. California Perinatal Quality Care Collaborative, Stanford, California
5. Department of Neurosurgery, Stanford University School of Medicine, Stanford, California
6. Division of Maternal-Fetal Medicine, Department of Obstetrics and Gynecology, Stanford University, Stanford, California