1. Faculty of Special Needs Education, Ludwigsburg University of Education, 71634 Ludwigsburg, Germany
2. Institut de Recerca Educativa, Departament de Pedagogia, Universitat de Girona, 17004 Girona, Spain
3. Special Olympics Europe Eurasia, Dublin 2, Ireland
4. Institute of Nursing and Health Research, Ulster University, Belfast BT1 6DN, Northern Ireland, UK