1. Toronto General Hospital Research Institute, University Health Network (UHN), Ontario, Canada (S.A., L.A., D.S.L., E.H.).
2. Institute of Health Policy, Management and Evaluation (IHPME) (S.A., L.A., D.S.L., E.H.), University of Toronto, Ontario, Canada.
3. Department of Pediatrics, Faculty of Medicine (L.B.), University of Toronto, Ontario, Canada.
4. Adult Congenital Heart Disease Program, University Heart Center, University Hospital Zurich, University of Zurich, Switzerland (L.M.M.).
5. Toronto Congenital Cardiac Centre for Adults, Peter Munk Cardiac Centre, UHN, Toronto, Ontario, Canada (M.O., E.H.).
6. Labatt Family Heart Centre, The Hospital for Sick Children, Toronto, Ontario, Canada (L.B.).
7. Biostatistics Research Unit, UHN, Toronto, Ontario, Canada (E.H.).