Footnotes

• Twitter @DrDebBateson, @wvnorman, @drhoggart

• Contributors DJB conceived and wrote the initial draft with input and editing from KIB. PAL, WVN, CM, KGD, PDB, LH, HWRL and ARAA provided key information and edits on each draft.

• Funding The authors have not declared a specific grant for this research from any funding agency in the public, commercial or not-for-profit sectors.

• Competing interests None declared.

• Patient and public involvement Patients and/or the public were not involved in the design, or conduct, or reporting, or dissemination plans of this research.

• Patient consent for publication Not required.

• Provenance and peer review Not commissioned; externally peer reviewed.