1. Faculty of Physical Culture and Health, University of Szczecin, Piastów 40b/6, 71-004 Szczecin, Poland
2. Faculty of Public Health & Policy, London School of Hygiene & Tropical Medicine, 15-17 Tavistock Place, London WC1H 9SH, UK
3. College of Graduate Health Studies, A.T. Still University of Health Sciences, 800 W. Jefferson St., Kirksville, MO 63501, USA
4. Faculty of Medicine, Biotechnology and Laboratory Medicine, Pomeranian Medical University, Rybacka 1, 70-204 Szczecin, Poland