1. Institute of Occupational Health and Sports Medicine of the Republic of Srpska, Centre Bijeljina , Bijeljina , Bosnia and Herzegovina
2. University of Belgrade Faculty of Medicine, School of Public Health and Health Management and Institute of Social Medicine , Belgrade , Serbia
3. University of Belgrade Faculty of Medicine, Institute of Epidemiology , Belgrade , Serbia
4. University of Belgrade Faculty of Medicine , Belgrade , Serbia
5. Serbian Institute of Occupational Health , Belgrade , Serbia