1. Department of Public Health and Primary Care, KU Leuven-University of Leuven, Leuven, Belgium;
2. Research Foundation Flanders, Belgium;
3. Child & Family, Brussels, Belgium;
4. Department of Paediatric Cardiology and
5. Division of Congenital and Structural Cardiology, University Hospitals Leuven, KU Leuven-University of Leuven, Leuven, Belgium;
6. The Heart Centre, Copenhagen University Hospital, Copenhagen, Denmark; and
7. Institute of Health and Care Sciences, University of Gothenburg, Gothenburg, Sweden