[1] Univ Oxford, Ethox Ctr, Oxford OX3 7LF, England
[2] Univ Oxford, Ethox Ctr, Eth & Engagement, Oxford OX3 7LF, England
[3] Univ Oxford, Oxford OX3 7LF, England
[4] Univ Oxford, Ethox Ctr, Bioeth, Oxford OX3 7LF, England
[5] Mahidol Univ, Bangkok 10700, Thailand
[6] Univ KwaZulu Natal, Sch Appl Human Sci, Psychol, Pietermaritzburg, South Africa
[7] Univ KwaZulu Natal, Sch Appl Human Sci, Pietermaritzburg, South Africa
[8] KEMRI Wellcome Trust Res Programme, Kilifi, Kenya
[9] Oxford Univ Clin Res Unit, Clin Trials Unit, Ho Chi Minh City, Vietnam
[10] Soc Nutr Educ & Hlth Act, Bombay, Maharashtra, India
[11] Childrens Hosp 1, Outreach & Int Dept, Ho Chi Minh City, Vietnam
[12] UCL, London WC1E 6BT, England
[13] Thammasat Univ, Fac Polit Sci, Bangkok, Thailand