Footnotes

• X @afaigenbaum, @a_garciahermoso, @sportingjim

• Contributors ADF and TRR conceptualised and drafted the initial version of the manuscript, with critical review provided by all authors.

• 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; externally peer reviewed.