1. Department of Pediatric Surgery, Medical University of Bialystok, Ulica Waszyngtona 17, 15-274 Bialystok, Poland
2. Department of Pharmaceutical Analysis, Medical University of Bialystok, Ulica Adama Mickiewicza 2D, 15-222 Bialystok, Poland
3. Department of Statistics and Medical Informatics, Medical University of Bialystok, Szpitalna 37, 15-295 Bialystok, Poland