1 Population Health Research Institute, St George's University of London, London SW17 0RE, UK. Electronic address: mrazai@sgul.ac.uk.
2 Aman Project LGBT Organisation, Istanbul, Turkey.
3 Rainbow Afghanistan, Bremen, Germany.
4 Institute of Medical and Biomedical Education, St George's University of London, London, UK.
5 Population Health Research Institute, St George's University of London, London SW17 0RE, UK; The Migrant Health Research Group, Institute for Infection and Immunity, St George's University of London, London, UK.