1. University of Novi Sad, Medical Faculty, Social Medicine , Hajduk Veljkova 3, 21000 Novi Sad , Serbia
2. Institute of Public Health of Vojvodina, Center for Analysis, Planning and Organisation of Health Care , Futoška 121, 21000 Novi Sad , Serbia
3. Institute of Public Health of Vojvodina, Center for Health Promotion , Futoška 121, 21000 Novi Sad , Serbia