1. Department of Health Promotion and Community Nursing, Faculty of Health Sciences, Medical University of Silesia, Katowice, Poland
2. Department of Human Nutrition, Faculty of Public Health, Medical University of Silesia, Katowice, Poland
3. The John Paul II Pediatric Center, Sosnowiec, Poland
4. Department of Rheumatology, The John Paul II Pediatric Center, Sosnowiec, Poland
5. Department of Biostatistics, Faculty of Public Health, Medical University of Silesia, Katowice, Poland
6. Department of Nephrology/ENDO MSWiA Hospital, Katowice, Poland