1. Department of Pediatrics, Division of Cardiology and Clinical Futures, The Children's Hospital of Philadelphia Perelman School of Medicine at The University of Pennsylvania Philadelphia Pennsylvania USA
2. Leonard Davis Institute For Healthcare Economics The University of Pennsylvania Philadelphia Pennsylvania USA
3. Center for Cardiovascular Outcomes, Quality, and Evaluative Research, Perelman School of Medicine The University of Pennsylvania Philadelphia Pennsylvania USA
4. Department of Internal Medicine, Division of Cardiology, The Hospital of The University of Pennsylvania Perelman School of Medicine at The University of Pennsylvania Philadelphia Pennsylvania USA
5. Department of Pediatrics, Division of Cardiology Washington University School of Medicine, and St. Louis Children's Hospital St. Louis Missouri USA