1. Department of Health Psychology and Research Methodology, Faculty of Medicine, P. J. Safarik University in Kosice , Kosice, Slovakia
2. Department of Community & Occupational Medicine, University Medical Center Groningen, University of Groningen , Groningen, The Netherlands
3. Institute of Applied Psychology, Faculty of Social and Economic Sciences, Comenius University in Bratislava Mlynské , Bratislava, Slovakia
4. Institute of Mathematics, Faculty of Natural Sciences, P. J. Safarik University in Kosice , Kosice, Slovakia