1 Head of Imperial College School of Medicine, Imperial College London, and consultant physician and endocrinologist, Imperial College Healthcare NHS Trust, London, England; a.sam@imperial.ac.uk ; ORCID: http://orcid.org/0000-0002-9599-9069 .
2 Clinical education fellow, Imperial College School of Medicine, Imperial College London, London, England; ORCID: https://orcid.org/0000-0001-7349-875X .
3 Vice dean (education), Faculty of Medicine, Imperial College London, and consultant obstetrician, Chelsea and Westminster Hospital, London, England.