1. Clinic for Pulmonology, University Clinical Center of Serbia, 11000 Belgrade, Serbia
2. Medical Faculty, University of Belgrade, 11000 Belgrade, Serbia
3. Institute for Medical Statistics and Informatics, Faculty of Medicine, University of Belgrade, 11000 Belgrade, Serbia
4. Institute for Cardiovascular Diseases “Dedinje”, 11000 Belgrade, Serbia
5. Center for Anesthesiology and Resuscitation, University Clinical Center of Serbia, 11000 Belgrade, Serbia
6. Clinic for Orthopedic Surgery and Traumatology, University Clinical Center of Serbia, 11000 Belgrade, Serbia