1. Center of Prevention and Rehabilitation; University of Cologne; Cologne Germany
2. Children's and Adolescent's Hospital; University of Cologne; Cologne Germany
3. Department of International; Health Maastricht University; School CAPHRI; Care and Public Health Research Institute; Maastricht the Netherlands
4. Cologne Center for Musculoskeletal Biomechanics (CCMB); University of Cologne; Cologne Germany