1. Agency for Public Health, Lazio Region, Rome, Italy
2. Sanofi Pasteur MSD, Lyon Cedex 07, France
3. INRCA, Department of Medical Oncology, Rome
4. Direzione Generale della Prevenzione Sanitaria, Ministero del Lavoro, della Salute e delle Politiche Sociali, via Giorgio Ribotta 5, 00144 Rome, Italy.
5. National Research Council, Institute of Research on Population and Social Policies, Rome, Italy