1. Department of Humanistic Sciences in Medicine, Wroclaw Medical University, ul. J. Mikulicza - Radeckiego 7, 50-368 Wroclaw, Poland
2. Department of Family Medicine, Wroclaw Medical University, ul. Syrokomli 1, 51-141 Wroclaw, Poland
3. Department of Psychiatry, Wroclaw Medical University, Wybrzeże L. Pasteura 10, 50-367 Wroclaw, Poland
4. Department of Statistics, Wroclaw University of Economics and Business, ul. Komandorska 118-120, 53-345 Wroclaw, Poland