1. Department of Occupational and Environmental Medicine Epidemiology and Hygiene, INAIL, Monte Porzio Catone, 00040 Rome, Italy
2. Research Center for Public Health, University of Milano-Bicocca, 20126 Milan, Italy
3. Asia Pacific Centre for Work Health and Safety, A World Health Organization Collaborating Centre in Occupational Health, University of South Australia, Adelaide, SA CA1-05, Australia
4. Centre for Organizational Health & Development, A World Health Organization Collaborating Centre in Occupational Health, University of Nottingham, Nottingham NG7 2RD, UK
5. Northern Kentucky University, Highland Heights, KY 41099, USA