1. School of Social and Community Medicine; University of Bristol; Bristol UK
2. Social and Mathematical Epidemiology Group; Department of Global Health and Development, London School of Hygiene and Tropical Medicine; London UK
3. Kirby Institute, University of New South Wales; Sydney Australia
4. Burnet Institute; Melbourne Australia
5. Health Protection Scotland; Glasgow UK
6. School of Health and Life Sciences; Glasgow Caledonian University; Glasgow UK
7. British Columbia Centre for Excellence in HIV/AIDS; University of British Columbia; Vancouver Canada
8. Blizard Institute; Queen Mary's University of London; London UK
9. Medical Research Institute; Ninewells Hospital, University of Dundee; Dundee UK