1. Department of Public Health, Faculty of Medicine, Semmelweis University, 1089 Budapest, Hungary
2. Faculty of Health Sciences, University of Pécs, 7621 Pécs, Hungary
3. Department of Neurosurgery, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
4. Department of Health Promotion Sciences, College of Public Health, The University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
5. Peggy and Charles Stephenson Oklahoma Cancer Center, Oklahoma City, OK 73104, USA
6. Department of Pulmonology, Semmelweis University, 1083 Budapest, Hungary