1 Centre for Population Health Sciences, University of Edinburgh, Edinburgh EH8 9AG, UK; Division of General Internal Medicine and Primary Care, Brigham and Women's Hospital, Harvard Medical School, Boston MA, USA. Electronic address: firstname.lastname@example.org.
2 Department of Primary Care and Public Health, School of Public Health, Imperial College London, London, UK.
3 WHO, Geneva, Switzerland.
4 Department of Health Policy and Management, Harvard School of Public Health, Boston, MA, USA.
5 Institute of Global Health Innovation, St Mary's Campus, London, UK.