1. Department of Internal Medicine, Diabetology and Nephrology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia , 40-055 Katowice , Poland
2. Liverpool Centre for Cardiovascular Science at University of Liverpool, Liverpool John Moores University and Liverpool Heart & Chest Hospital , Liverpool L69 3BX , UK
3. Students’ Scientific Association by the Department of Internal Medicine, Diabetology and Nephrology, Faculty of Medical Sciences in Zabrze, Medical University of Silesia , 40-055 Katowice , Poland
4. Faculty of Biomedical Engineering, Silesian University of Technology , 41-800 Zabrze , Poland
5. Department of Algorithmics and Software, Silesian University of Technology , 44-100 Gliwice , Poland
6. Danish Center for Health Services Research, Department of Clinical Medicine, Aalborg University , 9220 Aalborg , Denmark