1. University of Cologne, Medical Faculty and University Hospital , Center of Prevention and Rehabilitation , Cologne , Germany
2. University of Cologne, Medical Faculty and University Hospital , Department of Pediatrics , Cologne , Germany
3. Maastricht University , Department of International Health, School CAPHRI, Care and Public Health Research Institute , Maastricht , The Netherlands
4. Justus-Liebig University, UKGM , Department for Pediatric Neurology, Epileptology and Social Pediatrics , Giessen , Germany
5. University of Cologne, Medical Faculty and University Hospital , Cologne Centre for Musculoskeletal Biomechanics (CCMB) , Cologne , Germany
6. University of Oldenburg, Medical Faculty and University Hospital , Department of Pediatrics , Oldenburg , Germany