1. Pediatric Rehab Research Group, Rehabilitation Center for Children and Adolescents, University Children's Hospital Zurich, Affoltern am Albis, Zurich, Switzerland
2. CAPHRI Research Institute, Program Functioning and Rehabilitation, Department of Epidemiology, Maastricht University, Maastricht, Limburg, The Netherlands
3. Children's Research Center, University Children's Hospital Zurich, Zurich, Switzerland