1. Faculty of Medicine, University of Novi Sad, Novi Sad, Serbia
2. Clinical Department for Anesthesia, Intensive Care and Pain Management, Clinical Centre of Vojvodina, Novi Sad, Serbia
3. Department of Pharmacology, Toxicology and Clinical Pharmacology, Faculty of Medicine Novi Sad, University of Novi Sad, Novi Sad, Serbia
4. Department of Planning, Analysing and Statistics, Primary Health Care Center, Pančevo, Serbia