1. aDivision of Neonatology, The Children’s Hospital of Philadelphia, Philadelphia, Pennsylvania
2. bPerelman School of Medicine at the University of Pennsylvania, Philadelphia, Pennsylvania
3. cLeonard Davis Institute of Health Economics, Philadelphia, Pennsylvania
4. dDivision of Newborn Medicine, Department of Pediatrics, Harvard Medical School, Boston, Massachusetts
5. eDepartment of Neonatology, Beth Israel Deaconess Medical Center, Boston, Massachusetts
6. fVermont Oxford Network, Burlington, Vermont
7. gDepartment of Pediatrics, Larner College of Medicine, The University of Vermont, Burlington, Vermont
8. hDepartment of Mathematics and Statistics, The University of Vermont, Burlington, Vermont