1 Institute for Global Health, University College London, London, UK. Electronic address: r.burgess@ucl.ac.uk.
2 School of Social and Political Science, The University of Edinburgh, Edinburgh, UK.
3 Centre for Rural Health, School of Nursing and Public Health, University of KwaZulu-Natal, Durban, South Africa.
4 Alan J Flisher Centre for Public Mental Health, Department of Psychiatry and Mental Health, University of Cape Town, Cape Town, South Africa; Centre for Global Mental Health, King's Global Health Institute, Health Service and Population Research Department, Institute of Psychiatry, Psychology and Neuroscience, Kings College London, London, UK.