Official Statistics

Quality and methodology information for the sexually transmitted infections and National Chlamydia Screening Programme data release for England

Updated 10 June 2025

About this report

This report outlines the quality and methodology information (QMI) relevant to the sexually transmitted infections and National Chlamydia Screening Programme official statistics release published by the UK Health Security Agency (UKHSA). This QMI report supports users in understanding the strengths and limitations of these statistics, ensuring UKHSA is compliant with the quality standards stated in the Code of Practice for Statistics. The report covers the following areas:

1. The strengths and limitations of the data used to produce the statistics.
2. The methods used to produce the statistics.
3. The quality of the statistical outputs.

About the statistics

Sexually transmitted infections (STIs) are caused by a variety of organisms including bacteria, viruses and protozoa, which are primarily transmitted through sexual contact. STIs are a major public health concern due to the potentially severe impact on the health and wellbeing of individuals, the risks of antimicrobial resistance for bacterial STIs such as gonorrhoea, and pressures on healthcare services to provide testing and treatment. STIs are also a major source of health inequality given higher diagnosis rates among young people; gay, bisexual and other men who have sex with men (GBMSM); and some ethnic minority groups. If left undiagnosed and untreated, common STIs can cause a range of complications and long-term health problems including pelvic inflammatory disease, infertility, adverse pregnancy outcomes, neonatal infections, and irreversible cardiovascular and neurological damage.

The primary aim of England’s National Chlamydia Screening Programme (NCSP) is to reduce the reproductive harm of untreated infection in young women (and other people with a womb or ovaries) aged 15 to 24 years. As chlamydia is a largely asymptomatic infection, increases in the number of infections detected and treated is an indication of improved chlamydia control.

More information about STIs is available on the NHS website.

Geographical coverage: England

Publication frequency: Annual

Change log

3 June 2025: QMI report updated to reflect 2024 official statistics.

17 July 2024: QMI report updated with human papillomavirus (HPV) vaccination quality in the ‘Completeness’ section.

4 June 2024: QMI report first published.

Contact

Lead analyst: Dr Stephanie Migchelsen

Contact information: gumcad@ukhsa.gov.uk and ctad@ukhsa.gov.uk

Suitable data sources

Statistics should be based on the most appropriate data to meet intended uses.

This section describes the data used to produce the statistics.

Data sources

Two data sources are used for these official statistics.

Firstly, data on STI tests and diagnoses is submitted to UKHSA by all local authority commissioned sexual health services (SHSs) in England through the GUMCAD STI Surveillance System. GUMCAD is a pseudonymised and depersonalised data set of all face-to-face consultations, and remote (telephone and online) consultations at SHSs – this means that the data cannot be used to reveal anyone’s identity. STIs are not notifiable diseases, but reporting of STI tests and diagnoses using GUMCAD is mandatory as specified in the Department of Health and Social Care’s SHS service specification.

Secondly, data on all publicly provided chlamydia tests and diagnoses is submitted to UKHSA by primary diagnostic laboratories in England through the CTAD Chlamydia Surveillance System – this includes chlamydia testing provided outside of SHSs such as general practices (GPs) and pharmacies. CTAD is also a pseudonymised and depersonalised data set.

In combination, the data from GUMCAD and CTAD provides a comprehensive picture of STI service provision and diagnosis trends in England. These systems are detailed below.

GUMCAD

The GUMCAD STI Surveillance System was established in 2008 as an electronic surveillance system to collect pseudonymised, individual service user level data from SHSs. The data set includes:

• STI tests and diagnoses
• demographic data including age, ethnicity, gender identity and sexual orientation
• sexual behaviour
• outcomes of partner notification and management
• provision of HIV pre-exposure prophylaxis (PrEP)

Services reporting to GUMCAD

The following SHSs report GUMCAD data to UKHSA each quarter:

• SHSs providing specialist (Level 3) and non-specialist (Level 2) STI related care – these services may also provide SRH care as an integrated service
• online services providing non-specialist (Level 2) STI related care

Details on the levels of sexual health service provision are provided in Appendix B of the British Association for Sexual Health and HIV’s Standards for the Management of STIs.

CTAD

The CTAD Chlamydia Surveillance System is a universal disaggregate data set that collects chlamydia data from all laboratories commissioned by local authorities or the NHS to carry out chlamydia testing. This report includes the chlamydia data from tests and diagnoses occurring in community-based testing services.

Services reporting to CTAD

Chlamydia testing from all healthcare settings, covering community services (Level 1), non-specialist STI care services (Level 2) and specialist SHSs (Level 3).

Data quality

The data that we use to produce statistics must be fit for purpose. Poor quality data can negatively impact surveillance and can hinder effective decision making.

We have assessed the quality of the source data against the data quality dimensions in the Government Data Quality Framework.

This assessment covers the quality of the data that was used to produce the statistics, not the quality of the final statistical outputs. The ‘Quality summary’ section below assesses the quality of the final statistical outputs.

Strengths and limitations of the data

The following strengths of the data have been identified:

• CTAD and GUMCAD data reporting to UKHSA is mandatory so, in combination, it is a comprehensive source of STI testing and diagnoses in England
• CTAD and GUMCAD data are submitted quarterly and therefore provide timely data on STI testing and diagnoses (provisional counts of selected STI diagnoses are published quarterly), and reporters can retrospectively update previous submissions
• data validation rules (applied at the point of submission) ensure that all fields are completed properly
• additional data reviews, enhancement and quality assurance checks are carried out on a quarterly basis and for each annual official statistics release of STI and NCSP data
• test and diagnosis data is reported with depersonalised geographical information about where the tests were provided, and the area of residence of the person tested

The following limitations of the data have been identified:

• GUMCAD data is only reported by SHSs – a small number of people are tested for STIs in GPs but, in the case of chlamydia testing, these tests are reported by laboratories through CTAD
• CTAD and GUMCAD data is depersonalised, so it is not possible to identify individual people – it is not therefore possible to link individuals between data sets or to link people between different services within each data set
• neither data set collects data from private providers of sexual healthcare
• we cannot definitively rule out a small degree of over or under-reporting of activity or diagnoses due to miscoding by reporters – to mitigate this risk, we conduct data quality workshops, at least annually, with UKHSA’s regional Sexual Health Facilitators to review and improve the quality of data reported
• chlamydia tests and diagnoses in the NCSP statistics that are classified as ‘internet’ may be undercounted due to differences in how internet (online) data is reported between the CTAD and GUMCAD data sets – with reference to how CTAD and GUMCAD data is deduplicated (see ‘Completeness’ section below)

CTAD and GUMCAD are the most appropriate sources of data for these statistics. The design of both data sets helps ensure that the data is accurate and valid.

Accuracy

Accuracy is about the degree to which the data reflects the real world. This can refer to correct demographic and clinical data.

Every effort is made to ensure accuracy and completeness of the data, including web-based reporting with integrated checks on data quality. However, responsibility for the accuracy and completeness of data lies with the data submitter and service providers.

GUMCAD and CTAD data reporters are required to evaluate their own data content prior to submission to UKHSA to ensure that data is accurate and representative of their service provision. To further facilitate accuracy of reporting, UKHSA applies automated data validation rules at the point of submission that enforce data coding and formatting requirements. Data submissions that do not comply with the GUMCAD and CTAD data specification (as defined by the GUMCAD technical guidance and the CTAD technical guidance) may be rejected (where correction and resubmission is then required). Additionally, UKHSA conducts quarterly reviews of data content to ensure consistency in ongoing trends. Anomalies in trends are followed up directly with data reporters to either confirm the data content is correct, or to ensure corrected data is resubmitted.

Completeness

Completeness describes the degree to which records are present.

For a data set to be complete, all records are included, and the most important data is present in those records. This means that the data set contains all the records that it should and all essential values in a record are populated.

Completeness is not the same as accuracy as a full data set may still have incorrect values.

CTAD and GUMCAD only contain mandatory fields, all of which must be completed in order to submit data. This ensures that all the necessary information is recorded for each service or test provided, but reporters may report some data as either ‘not known’ or ‘not specified’ (which would be classified as ‘incomplete’ data).

Chlamydia tests and diagnoses are recorded in both CTAD and GUMCAD data sets for specialist (Level 3) SHSs. Chlamydia tests and diagnoses from these services are deduplicated when combining CTAD (Level 1 and Level 2) and GUMCAD (Level 3) data as part of data calculation to prevent overestimation of tests or diagnoses.

Data is updated on an annual basis due to SHS or laboratory resubmissions and improvements to data calculation. Therefore, data presented in statistical outputs may differ from previous publications.

The tables below show trends in key demographic data quality for CTAD and GUMCAD presented by the percentage of data completeness (data reported with a specified value).

GUMCAD

Table A1. Number of consultations at sexual health services in England and percentage completeness of demographic data, 2015 to 2024 (GUMCAD)

Demographic variables	2015	2016	2017	2018	2019	2020	2021	2022	2023	2024
Number of consultations	3,139,834	3,223,822	3,334,828	3,631,445	3,869,725	3,573,476	4,057,195	4,415,030	4,630,665	4,505,785
Age (%)	99.9	99.9	99.9	99.9	99.9	100	100	100	100	100
Country of birth (%)	87.9	87.3	85.7	81.4	80.1	78.8	79.9	84.8	91.5	90.7
Ethnicity (%)	95.3	95	93.4	91.2	91.1	89.6	91.3	92.3	94	94.5
Gender identity (%)	99.4	99.1	99	98.6	98.3	97.6	96	94.8	95.8	95.7
Sexual orientation (%)	90.3	90	87.4	85.9	88	90.5	89.8	91.2	91.3	91

The table shows trends in data quality by showing the percentage complete (reported with a specified value as compared to ‘not known’ or ‘not specified’) for each demographic variable by year.

Missing submissions

No missing submissions for 2015 to 2024.

Imputed data

The number of STI diagnoses among GBMSM in 2021, as presented in the accompanying data tables, is unadjusted and underestimated because of incomplete data quality that year – but the overall trend in diagnoses in all people (irrespective of gender and sexual behaviour) is unaffected. Please refer to the ‘Technical note’ in the main report for further details.

GUMCAD data may be imputed (estimated) where there are gaps in total coverage due to late submissions or data quality issues. Data is imputed by using the most recent quarterly submission as an appropriate proxy to maintain current trends (based on data reported since 2008 and given the increasing trends in STI tests and diagnoses since then, this is usually a conservative assumption). Imputed data is replaced with real data submissions in the next available data release.

No data was imputed in 2024.

Based on findings from a clinical chart audit, we know that the number of HPV vaccinations has been substantially under-reported due to miscoding or delayed software upgrades in the electronic patient management systems of some SHSs.

CTAD

Table A2. Number of chlamydia tests in young people aged 15 to 24 years from non-specialist sexual health services or community settings in England and percentage of demographic data completeness, 2015 to 2024 (CTAD)

Demographic variables	2015	2016	2017	2018	2019	2020	2021	2022	2023	2024
Number of chlamydia tests	960,506	832,621	717,728	690,822	713,118	554,185	569,699	600,430	571,551	496,759
Gender	98.7	98	98.6	99	99.1	99.4	99.2	98.6	97.6	95.6
Age	99.6	99.9	99.8	99.7	99.8	99.8	100	99.9	99.9	99.9
Postcode of residence – non-specialist	85.6	85.1	88.2	89	90	93.3	92.5	92.3	91.6	91
Ethnicity – non-specialist	49.2	51.1	56.2	59.4	63.9	70.2	71.8	70	69.6	70.7
Testing service type	98.4	97.7	97.3	98	97.2	97.5	97.9	98.5	98.4	98.3

Missing submissions

Table A3. CTAD missing submissions from 2016 to 2024

Laboratory	UKHSA region	Period missing
Leeds General Infirmary Laboratory	Yorkshire and The Humber	July to September (quarter 3) 2016
Birmingham Women’s Laboratory	West Midlands	October to December (quarter 4) 2018
Harrogate District Hospital Laboratory	Yorkshire and The Humber	July to December (quarter 3 to 4) 2024
The Princess Alexandra Hospital	East	October to December (quarter 4) 2024

Uniqueness

Uniqueness describes the degree to which there is no duplication in records. This means that the data contains only one record for each entity it represents, and each value is stored once.

The CTAD and GUMCAD teams conduct deduplication as part of quarterly data enhancement routines and management to ensure that tests and diagnoses are only counted once within a single episode of patient care (to prevent double-counting). GUMCAD also completes probabilistic matching to identify potential duplicates between online and face-to-face SHSs from 2021 onwards – where some service users may need to visit a face-to-face SHS for treatment following a chlamydia or gonorrhoea diagnosis by an online SHS. (Data prior to 2021 is unaffected.) A total of 2.8% of chlamydia diagnoses and 3.6% of gonorrhoea diagnoses in England in 2024 were identified as potential duplicate reports between online and face-to-face SHSs – and were removed from the total counts for these STIs. Confirmed syphilis diagnoses can only be reported by face-to-face SHSs, so there are no potential duplicate syphilis diagnoses.

Given the depersonalised nature of CTAD and GUMCAD data, unique individuals are identified (within each data set) using an alphanumeric code (patient ID) issued by their SHS – without revealing their identity. This enables UKHSA to assess testing and diagnoses in unique individuals within a single SHS but not between different SHSs. This is an acceptable limitation to ensure public trust in the confidentiality of SHSs and the GUMCAD data they report to UKHSA – especially as SHSs are regarded as anonymous access providers under the Health and Social Care (Safety and Quality) Act 2012.

Consistency

Consistency describes the degree to which values in a data set do not contradict other values representing the same entity.

For example, there are multiple internal validation checks within GUMCAD to ensure consistency – such as ensuring that the consultation dates reported within each quarterly submission are restricted to the relevant dates within each quarter and that dates reported span the full length of quarter (from the start of the quarter to the end of the quarter).

CTAD data is based on tests with confirmed positive and negative results only. Tests with equivocal, inhibitory, and insufficient results have been excluded as most people with these results are retested.

It is possible that the number of diagnoses used to calculate the chlamydia detection rate indicator for (all) persons has a different value than the total of women and men diagnoses. This is because the total number of diagnoses includes tests where sex or gender was reported as indeterminate or unspecified.

Data reported with an unknown gender identity may be included in the data total (therefore the total may not equal the sum of women and men). In STI and NCSP statistical products, data is presented in relation to gender identity – which may, or may not, be the same as sex registered at birth. Gender identity refers to a person’s sense of their own gender – whether male (men), female (women) or any other identity (such as non-binary).

Timeliness

Timeliness describes the degree to which the data is an accurate reflection of the period that it represents, and that the data and its values are up to date. 

Data is timely if the time lag between collection and availability is appropriate for the intended use. Both CTAD and GUMCAD data is reported to UKSHA on a quarterly basis – which minimises the reporting burden for providers while providing sufficiently timely STI surveillance data to guide local, regional and national public health action, and to support the commissioning of SHSs and chlamydia screening. CTAD and GUMCAD submission deadlines are set 6 weeks after the end of each quarter. This allows SHSs and laboratories sufficient time to process test results and ensure that data entry is complete, which facilitates a high rate of timely submissions. If there are gaps in submissions that would negatively impact data reporting, GUMCAD data is imputed (estimated) to ensure it is a more complete reflection of annual trends (please see the ’Completeness’ section for more information on imputed data). Provisional counts of selected STI diagnoses are published quarterly.

Validity

Validity describes the degree to which the data is in the range and format expected.

Detailed technical guidelines are available for both CTAD and GUMCAD that clearly define the data coding and formatting requirements. Additionally, automated data validation rules are applied at the point of submission which enforce the data coding and formatting requirements. Data that does not comply may be rejected (where correction and resubmission is then required).

Sound methods

Statistical outputs should be made using the best available methods and recognised standards.

This section describes how the statistics were produced and quality assured.

Data set production

The official statistics are produced using automated calculations in standard software packages (such as Stata, SQL, MS Access and MS Excel) which reduces the risk of human error via manual calculations. All calculations are independently verified via multiple quality assurance checks.

Quality assurance

CTAD and GUMCAD data go through a rigorous data validation and evaluation process. The initial data submissions have automated data validation rules applied at point of submission (enforcing coding and formatting requirements) and are also subject to quarterly data enhancement routines and quality assurance checks (such as deduplication of test and diagnosis data and ensuring consistency in data trends).

All statistical products for these official statistics are produced using automated calculations which are prepared and tested in advance. Additionally, each statistical product is produced by a member of the CTAD or GUMCAD team, which is then independently validated by another member of the team. Regional breakdowns are also reviewed by regional UKHSA colleagues (the Field Service epidemiology scientist and Sexual Health Facilitator for each region). Steps are taken to ensure the accuracy of calculations and the written text in the report. Any data queries that are raised via review are investigated and actioned appropriately – where data may be confirmed as correct or may require the addition of specific data notes or caveats to explain the data content. All of these quality assurance checks ensure that outputs are robust and reliable.

Confidentiality and disclosure control

UKHSA’s responsibilities include collecting surveillance data on STIs. We use this information to help improve the nation’s sexual health and wellbeing, to understand more about people’s access to care and the effectiveness of interventions such as PrEP or HPV vaccination, and to monitor outbreaks of STIs and HIV across the nation.

The sexual health and HIV privacy notice explains the STI surveillance that we conduct and how we use the data from these surveillance systems. All UKHSA staff with access to surveillance data must complete mandatory information governance training, which must be refreshed every year. Information is stored on computer systems that are kept up-to-date and regularly tested to make sure they are secure and protected from viruses and hacking. UKHSA staff do not store data on their own laptops or computers. Instead, data is stored on secure, restricted access UKHSA servers.

CTAD and GUMCAD data is both pseudonymised and depersonalised data sets – this means that this data cannot be used to reveal anyone’s identity. Additional controls are applied to the outputs included in the official statistics to minimise the risk of deductive disclosure. These controls include the masking of small numbers (counts of 1 to 4) when the relevant population size is less than 10,000 people. These controls are described in UKHSA HIV and STI data publication guidelines.

Geography

The data in these official statistics is provided at national (England), regional (UKHSA Regions), and upper and lower tier local authority level. All local authority level data is published to the Sexual and Reproductive Health and Public Health Outcomes Framework Profiles, while regional and national data is provided in the report, data tables, and slide set.

Most UKHSA Regions are consistent with the former Government Office Regions (GORs). The major difference between regions is Milton Keynes, which is in the UKHSA South East region, but is in the East of England GOR.

Quality summary

The Code of Practice for Statistics states that quality means that statistics:

• fit their intended uses
• are based on appropriate data and methods
• are not materially misleading

Quality requires skilled professional judgement about collecting, preparing, analysing, and publishing statistics and data in ways that meet the needs of people who want to use the statistics.

This section assesses the statistics against the European Statistical System dimensions of quality.

Relevance

Relevance is the degree to which the statistics meet user needs in both coverage and content.

There is a clear need for timely, high quality STI and NCSP statistics. Google Analytics data shows that during 2024, the STI and NCSP statistics were viewed nearly 19,989 times. The statistics are used to monitor trends and inequalities in STIs, the coverage of chlamydia screening through the NCSP, and the impact of public health interventions such as human papillomavirus vaccination and HIV PrEP.

The statistics are published annually to prioritise completeness and accuracy of reporting. England has experienced rising rates of STIs since the early 2000s, with the largest annual number of diagnoses of gonorrhoea reported in 2023.

The STI and NCSP statistics are primarily used by people in local public health teams, and by the providers and commissioners of SHSs and chlamydia screening in local authorities. The uses of this data include monitoring of trends including inequalities in STIs, evaluation of interventions, local strategic needs assessments and commissioning.

We have continued to make changes to the publication to meet user needs. We now publish the following products as part of the statistical release:

1. Sexually transmitted infections and screening for chlamydia in England: 2024 report.
2. Sexually transmitted infections (STIs): annual data tables.
3. NCSP: chlamydia testing data in young people aged 15 to 24 years in England, 2015 to 2024.
4. STI in England slide set.
5. Sexual and Reproductive Health Profiles: STI and NCSP data by local authority.
6. Public Health Outcomes Framework: STI and NCSP data by local authority.
7. This QMI report, first published in June 2024.

By providing this range of different outputs, we can better cater to the needs of different users from a range of backgrounds, in line with the Office for National Statistics user personas.

UKHSA regularly meets with key sexual health stakeholders to share epidemiological updates on STIs and to understand how to best meet their needs. This includes meetings with the English Sexual Health and HIV Commissioners’ Group, and with the British Association for Sexual Health and HIV (BASHH). These discussions are used to inform the data we publish through official statistics.

Accuracy and reliability

Accuracy is the proximity between an estimate and the unknown true value. Reliability is the closeness of early estimates to subsequent estimated values.

The accuracy of the statistics is largely dependent on the accuracy of the source data submitted by SHSs and laboratories. We have assessed the source data to be accurate (see the ‘Data quality’ section) as the design of CTAD and GUMCAD helps prevent data entry errors, and guidance given to users helps ensure the right information is collected in the proper format. The statistics report on STI testing and diagnoses at all local-authority commissioned SHSs. The statistics therefore represent all STI diagnoses at SHSs in England.

Timeliness and punctuality

Timeliness refers to the time gap between publication and the reference period. Punctuality refers to the gap between planned and actual publication dates.

These official statistics aim to provide timely and up-to-date figures of important epidemiological indicators to inform ongoing STI control efforts in England.

The statistics are always published as soon as possible, allowing for the collection of data submissions, production and quality assurance. The final CTAD and GUMCAD deadlines for submission of all data (January to December) to UKHSA is mid-February each year after which they undergo extensive validation by members of the national and regional teams.

These official statistics are pre-announced at least 28 days in advance, in line with the Code of Practice for Statistics. The provisional publication date for the official statistics is pre-announced online in December and can be found on the UKHSA release calendar.

Provisional counts of selected STI diagnoses are published quarterly.

Accessibility and clarity

Accessibility is the ease with which users can access the data, also reflecting the format in which the data is available and the availability of supporting information. Clarity refers to the quality and sufficiency of the metadata, illustrations and accompanying advice.

We publish a number of different statistics products as part of the release, as stated in the relevance section. This means that users can access the statistics in a format and style that best suits their needs.

The official statistics are made available in a range of media (such as HTML and ODS) which optimise accessibility across different devices (such as desk top computers and smart phones) and different operating systems (such as Microsoft and Apple). The content has also been designed to be accessible for users with visual impairments. For example, the data and data notes are presented in a way that is compatible with a data reader, and graphics are designed in a way that is accessible to people who are colour-blind (such as using sufficient contrast between colour gradients).

The GOV.UK accessibility statement explains some of the accessibility features for HTML web pages.

Coherence and comparability

Coherence is the degree to which data that is derived from different sources or methods, but refers to the same topic, is similar. Comparability is the degree to which data can be compared over time and domain.

Data included in these and other STI reports published on GOV.UK has been collected in a consistent manner over time using surveillance data sets with approved Information Standards Notices from NHS England (formerly NHS Digital). GUMCAD data has been reported since 2008, and CTAD data has been reported since 2012. Figures reported in 2020 and 2021 are notably lower than previous years due to the disruption to SHSs during the national response to the COVID-19 pandemic.

Trade-off between timeliness and completeness

There is a trade-off between timeliness and completeness for the statistics. Given the high-profile nature of these statistics, we may allow additional time for reporters to submit data after the deadline or to resubmit corrected data following queries raised as part of data validation and quality assurance. We also ensure there is sufficient time for validation of all outputs.

Uses and users

Users of statistics and data should be at the centre of statistical production, and statistics should meet user needs.

This section explains how the statistics are used, and how we understand user needs.

Appropriate use of the statistics

This data is reported as diagnosis numbers and rates because they are restricted to data on STIs diagnosed at SHSs, while the NCSP data is based on data from all local authority commissioned settings providing chlamydia testing. Users therefore should not use these statistics as a direct measure of STI incidence in the general population for the following reasons:

• many people with STIs do not experience any symptoms and may not seek testing (opportunistic asymptomatic screening is only provided for chlamydia through the NCSP which, to reduce reproductive harm, is targeted to young women only)
• some people with STI related symptoms may find it difficult to access STI testing
• while most STI testing is provided at SHS, some testing occurs in other settings such as GPs (chlamydia testing from GPs is captured via CTAD, but that is not the case for other STIs such as gonorrhoea) or via private providers

There are several important factors to consider when comparing STI trends over time. These include:

• the recommendation for asymptomatic screening of gay, bisexual and other men who have sex with men at multiple anatomical sites (genital, rectal and pharyngeal) led to an increase in detection of STIs in this population in the early 2010s; there was also more testing for STIs using more sensitive diagnostic tests at this time, which also contributed to an increase in diagnoses, but it is unlikely that these factors would have been the main drivers for increasing trends in STIs since the mid to late 2010s
• several factors have contributed to the rise in STIs in the period covered by these official statistics; these include behavioural factors such as less condom use as well as structural factors such as increased demand for sexual health services
• disruption to service delivery during the first year of the COVID-19 pandemic led to reduced testing and fewer STI diagnoses
• the scale up of online postal self-sampling services to test for STIs increased during 2020 and 2021; this has led to an increase in testing but there is evidence of inequalities in the use of online services by residential area-level deprivation

Known uses

We are aware that the statistics are used in several different ways, including:

• monitoring STI trends and inequalities in STIs
• joint strategic needs assessments for local authorities
• commissioning of sexual health services and chlamydia screening
• health promotion
• research
• teaching

Known users of the statistics are primarily in local authorities, providers of sexual healthcare, charities, academia and research.

User engagement

We undertake a broad range of different user engagement activities to ensure we fully understand our users and their needs. These include, but are not limited to:

• regular meetings with key stakeholders including local authority commissioners
• regular meetings with the English Sexual Health and HIV Commissioners’ Group
• regular meetings with the British Association for Sexual Health and HIV (BASHH)
• regular care pathway workshops with local providers and their commissioners
• hosting an annual meeting with clinical stakeholders to discuss the epidemiology of gonorrhoea and Mycoplasma genitalium and associated antimicrobial resistance
• regular contact with various sexual health charities
• teaching at undergraduate and postgraduate level
• developing e-courses with BASHH
• providing statistics for individual clinics
• completing data requests from academic researchers as well as internal and external stakeholders, including the president of BASHH
• contributing to Parliamentary Questions and Chief Medical Officer briefings
• producing publicly available slide sets for educational use
• giving presentations at leading national sexual health and public health conferences such as the annual British Association for Sexual Health and HIV (BASHH) and UKHSA conferences

We have worked with stakeholders to develop and improve our outputs based on user feedback. For example, we have published, as official statistics in development, data on STI testing by symptomatic status. We have continued to innovate and improve on these statistical products, for instance by updating some of the visualisations of the data in our statistical products.

Related statistics

Further STI data is available on the UKHSA STI annual data tables web page in the form of the annual report, data tables, slide set and an infographic.

Further data on chlamydia tests and diagnoses in young people aged 15 to 24 years is available on the UKHSA NCSP annual data tables web page.

Interactive tables, charts, and maps showing local area STI data are available on the Sexual and Reproductive Health Profiles.

Provisional data on selected STIs is available on the STI quarterly surveillance reports: provisional data.

Further information on the GUMCAD and CTAD Surveillance Systems.

Further information on the Gonococcal Resistance to Antimicrobials Surveillance Programme (GRASP).

Further information on Mycoplasma genitalium Antimicrobial Resistance Surveillance (MARS).

Further information on trends in mpox.

Further information on trends in HIV diagnoses in the UK.

For the latest lymphogranuloma venereum (LGV) surveillance data for the UK.

For the latest guidance and data on Shigella spp.

For further information on pelvic inflammatory disease (PID).

STIs in other nations of the UK and internationally

Most health protection functions in the UK are devolved to the other UK nations’ public health agencies. Public Health Scotland publishes STI reports such as the report on gonorrhoea, while Public Health Wales publishes annual data as does the Public Health Agency of Northern Ireland.

The European Centre for Disease Prevention and Control publishes annual STI reports with data from counties in the European Union and European Economic Area (EU and EEA). Many European countries also publish annual STI reports, such as the report from the Netherlands. As was the case for many countries of the EU and EEA, there was a sharp rise in many STIs between 2021 and 2022 in England. This was particular pronounced for gonorrhoea with the largest proportional rise (by age group) among young people.

The US Centers for Disease Control and Prevention also publishes STI reports, and the World Health Organization publishes estimates of global and regional STI trends.

Comparisons of STI trends between countries must be made with caution because the level of sexual health provision and STI testing, as well as the comprehensiveness of surveillance systems, vary between countries. For instance, the number of gonorrhoea diagnoses made in England in 2022 exceeded the total reported across the EU and EEA that year, but this is because there is more comprehensive ascertainment of STIs in England. This more comprehensive ascertainment is a result of the fact that England has dedicated sexual health services which provide open access STI testing and treatment, all of which report GUMCAD data to UKHSA.