1 | Center for Health Services Research, Department of Hygiene, Epidemiology and Medical Statistics,School of Medicine, National and Kapodistrian University of Athens, Athens, Greece |
2 | Center for Global Tobacco Control, Department of Social and Behavioral Sciences, Harvard School of Public Health, West Boston, USA |
3 | Smoking and Lung Cancer Research Center, Hellenic Cancer Society, Athens, Greece |
4 | Foundation for Biomedical Research of the Academy of Athens, Athens, Greece |
5 | Department of Environmental Health, Harvard School of Public Health, West Boston, USA |