1. VA HSR&D Center for Innovations in Quality, Effectiveness and Safety, Michael E. DeBakey VA Medical Center, Houston, TX, USA.
2. Department of Medicine, Health Services Research Section, Baylor College of Medicine, Houston, TX, USA.
3. Epidemiology and Health Outcomes Research Unit, Division of Neonatology, Department of Pediatrics, Stanford University School of Medicine and Lucile Packard Children’s Hospital, Palo Alto, CA, USA.
4. California Perinatal Quality Care Collaborative, Palo Alto, CA, USA.