1 Clinical Epidemiology and Medical Statistics Unit, Department of Biomedical Sciences, Research, Medical Education and Professional Development Unit, University of Sassari, Sassari, Italy.
2 USAID Georgia TB Prevention Project, University Research Co., LLC Branch in Georgia, Tbilisi, Georgia.
3 World Health Organization Collaborating Centre for TB and Lung Diseases, Fondazione S. Maugeri, Care and Research Institute, Tradate, Italy.