Footnotes

• BL and CRM are joint senior authors.

• Twitter @CattyRM

• Collaborators On behalf of the INPIC Group: John Ellershaw, Hugh Antrobus, Austin Leach, Heino Hugel, Jo Byers, Gary Jeffers, Paul Cook and Peter Walton.

• Contributors BL drafted the initial letter and revised this with CRM. JB, NC and MLS reviewed and revised the draft letter. CRM, BL, MM, JB, KS, NC, MW and MLS all approved the final, submitted version.

• 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 consent for publication Not required.

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