1. Department of Pediatrics, University of Cincinnati College of Medicine, Cincinnati, Ohio.
2. Division of Neonatal and Pulmonary Biology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
3. Department of Anesthesiology, University of Cincinnati College of Medicine, Cincinnati, Ohio.
4. Division of Pain and Palliative Medicine, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
5. Division of Biostatistics and Epidemiology, Cincinnati Children's Hospital Medical Center, Cincinnati, Ohio.
6. St. Elizabeth Hospice, St. Elizabeth Healthcare, Edgewood, Kentucky.