Bibliographical noteFunding Information:
The views expressed are those of the author(s) and not necessarily those of the NHS, the NIHR or the Department of Health. Declaration of personal interests: None.
RH is supported by the Gastrointestinal and Liver Disorder theme of the NIHR Nottingham Biomedical Research Centre (Reference no: BRC‐1215‐20003). JRM receives salary support from a Medical Research Council Clinician Scientist Fellowship [grant number MR/P008348/1].