Footnotes

• Collaborators The members of the GUMCADv3 Steering Group are as follows: Afra Barrett, Jackie Cassell, Laura Clark, Claudia Estcourt, Iain Galloway, Nigel Field, Patti Green, James Hardie, Leigh Holmes, Peter Horne, Gwenda Hughes, Hamish Mohammed, Monty Moncrieff, Anthony Nardone, David Phillips, David Stuart, Ann Sullivan and Sonali Wayal.

• Ethics statement As GUMCADv2 is a routine public health surveillance activity, no specific consent was required from the patients whose data were used in this analysis. PHE has permission to handle data obtained by GUMCADv2 under section 251 of the UK National Health Service Act of 2006 (previously section 60 of the Health and Social Care Act of 2001), which was renewed annually by the ethics and confidentiality committee of the National Information Governance Board until 2013. Since then the power of approval of public health surveillance activity has been granted directly to PHE.

• Funding Public Health England (Innovation Fund).

• Competing interests None declared.

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

• ▸ Acknowledgements and Contributors to this paper are available online at http://sti.bmj.com