Footnotes

• Contributors MM provided the concept for the letter and steered the overall IRTB it was based on, as well as collecting the information and writing it. GT, HL and AW all provided input based on their individual SME areas and assisted in reviewing the finished letter. MS provided oversight, contributed input based on his individual SME area and editing the letter.

• 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.

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