Footnotes

• X @drnatarmstrong

• Contributors NA conceptualised the paper and led the writing of the first draft. ST-P reviewed the draft and contributed substantially to revising it. NA acts as guarantor.

• 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 Both authors are current members of the UK National Screening Committee.

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