1 The Lancet, London EC2Y 5AS, UK. Electronic address: jessamy.bagenal@lancet.com.
2 National Institute for Health and Care Excellence, London, UK.
3 Paediatric Surgery Unit, Lagos University Teaching Hospital, Lagos, Nigeria.
4 Institute of Applied Health Research, University of Birmingham, Birmingham, UK.
5 Hospital Español de Veracruz, Veracruz, Mexico.
6 Department of Anaesthesia and Perioperative Medicine, Groote Schuur Hospital and the University of Cape Town, Western Cape, South Africa.
7 Institute of Clinical Epidemiology and College of Medicine, National Institutes of Health, University of the Philippines Manila and Philippine General Hospital, Manila, Philippines.
8 Department of Anaesthesia Medical College, Aga Khan University, Nairobi, Kenya.