1. Unit of Cancer Epidemiology, Belgian Cancer Centre, Scientific Institute of Public Health , Brussels, Belgium
2. Department of Human Structure and Repair, Faculty of Medicine and Health Sciences, University Ghent , Ghent, Belgium
3. Cancer Epidemiology Research Program, Catalan Institute of Oncology–IDIBELL, L’Hospitalet de Llobregat , Barcelona, Spain
4. Centro de Investigación Biomédica en Red: Epidemiología y Salud Pública (CIBERESP CB06/02/0073) , Madrid, Spain
5. Unit for Vaccination Programmes, Public Health Agency of Sweden , Stockholm, Sweden
6. Department of Women’s and Children’s Health, Karolinska Institutet , Stockholm, Sweden
7. International Agency for Research on Cancer , Lyon, France