1. Children and Adolescent Health, Aarhus University Hospital, Aarhus, Denmark;
2. Department of Women’s and Children’s Health, Uppsala University, Sweden;
3. Children's Hospital, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland;
4. Department of Pediatrics and Adolescent Medicine, Turku University Hospital and Turku University, Turku, Finland;
5. Department of Pediatrics, Kuopio University Hospital, Kuopio, Finland;
6. PEDEGO Research Center and Medical Research Center Oulu, University of Oulu, and Department of Children and Adolescents, Oulu University Hospital, Oulu, Finland;
7. Department of Pediatrics and Adolescent Medicine, University Hospital Rigshospitalet, Copenhagen, Denmark