Table 1

Sampling details for sentinel sites

Laboratory	Clinics	Location	Attendance dates of sample collection	No of samples	Total GBMSM attendees at clinic over time period of sample collection	% of clinic population sampled
The Doctor’s Laboratory North London	Central Middlesex Hospital, Northwick Park Hospital, Tudor Centre	London	01 Nov 2017–28 Dec 2017 and 02 Jul 2018–28 Sep 2018	450	995	45.2
Homerton Hospital	Homerton Hospital	London	09 Jan 2018–11 Jul 2018	566	2007	28.2
Imperial/St Mary’s Hospital	Jefferiss Wing Centre for Sexual Health	London	06 Aug 2018–17 Oct 2018	467	1200	38.9
St Thomas’ Hospital	Burrell Street Sexual Health Clinic, Streatham Hill Primary Health Care Centre, Walworth Sexual Health Clinic	London	01 Oct 2018–31 Dec 2018	643	3357	19.2
Leeds Teaching Hospitals Trust	Leeds Sexual Health	Leeds	01 Apr 2017–13 Jul 2017	451	969	46.5