1. Department of General Orthopaedics, Musculoskeletal Oncology and Trauma Surgery, Poznan University of Medical Sciences, 61-701 Poznan, Poland
2. The Faculty of Educational Studies, Kazimiera Milanowska College of Education and Therapy, 61-473 Poznan, Poland
3. Center for Early Intervention of the Polish Association for People with Intellectual Disabilities in Poznan, 61-446 Poznan, Poland
4. Department of Pedagogy and Psychology, University of Security, 60-778 Poznan, Poland