University College London - Institute for Global Health, University of Ibadan - Department of Paediatrics, University of Melbourne - Department of General Medicine, University of Ibadan, University College Hospital Ibadan, Independent, University of Pittsburgh, University College London, Save the Children International, Nigeria, Save the Children International, Nigeria, Save the Children International, Nigeria, Save the Children International, Nigeria, Save the Children, UK, Save the Children, UK, Save the Children, UK, GlaxoSmithKline, University of Ibadan, University College London, Karolinska Institutet - Department of Global Public Health and Independent

London School of Hygiene & Tropical Medicine, University College London, affiliation not provided to SSRN, affiliation not provided to SSRN, University College London and University College London