1. Department of Medical Physics; University of Wisconsin; Madison WI USA
2. Institute of Preventive Pediatrics; Faculty of Sport and Health Sciences, and German Heart Center, Department of Pediatric Cardiology and Congenital Heart Defects; Munich Germany
3. Division of Cardiology, Department of Pediatrics; Children's Hospital of Wisconsin-Milwaukee and Fox Valley; Milwaukee WI USA
4. Division of Cardiology, Department of Pediatrics, Children's Hospital Colorado; The University of Colorado School of Medicine; Denver CO USA
5. Division of Cardiology, Department of Pediatrics; Lurie Children's Hospital; Chicago Illinois USA
6. Division of Cardiology, Department of Pediatrics; Hope Children's Hospital; Oak Lawn IL USA