1. General information about these data sources

Supplier information 

The UK Health Security Agency (UKHSA) is responsible for protecting every member of every community from the impact of infectious diseases, chemical, biological, radiological and nuclear incidents and other health threats. They provide intellectual, scientific and operational leadership at national and local level, as well as on the global stage, to make the nation's health secure. UKHSA is an executive agency, sponsored by the Department of Health and Social Care.

Legal basis for sharing data

The legal basis for sharing these data is Section 45a of the Statistics and Registration Service Act (SRSA) 2007 as amended by the Digital Economy Act 2017.

This excludes the National Radiotherapy and Systemic Anti-Cancer Therapy (SACT) data feeds, which were supplied under Control of Patient Information (COPI) regulations.

Ethical scrutiny

ONS statisticians complete an ethical assessment of all proposed uses of a data source before work begins, and before they are given permission to access the data by the ONS Information Asset Owners (IAO). IAOs are senior ONS officials who are responsible for data sources, including protecting confidentiality and ensuring appropriate use.

For some new uses, notably where there may be more challenging ethical concerns, ONS statisticians will seek advice and ethical approval from the National Statistician’s Data Ethics Advisory Committee (NSDEC). Committee members have relevant expertise, provide scrutiny and challenge, and crucially, are independent.

Ethical scrutiny often involves exploring the balance between any data protection risks and the public good that could come from the new work. Most importantly, this scrutiny helps the ONS to ensure that we consider carefully whether we should produce a new statistic or not.

Minutes are published so the committee's views and approvals are transparent and available for the public to see. More information on the ethics self-assessment tool used by ONS researchers, and the NSDEC, can be found on the UK Statistics Authority's website.

Links to relevant NSDEC minutes are included for each dataset.

Data protection

Data Protection Impact Assessments (DPIAs) are completed for all uses of data where there are inherent risks for processing personal data, for example, when processing large volumes of personal data or when processing personal data of a sensitive nature. The DPIA ensures appropriate controls are in place to minimise risks and to provide assurance around the safety of the data.

Access to data held within the ONS Data Access Platform (DAP) is only granted to security-cleared ONS researchers on a case-by-case basis. This is done through a request process, which provides a business justification, authorised by the ONS IAO with advice from the Security and Information Management team.

Access is given via a “project space”, which includes only the data required to carry out the analysis that has been approved, and only to the users who require access to those data. Users are not permitted to access direct identifiers (such as name, address, date of birth, or sex) for the purposes of analysis. Access to identifiers is limited to a smaller number of staff who are specially trained and only for the purposes of data linkage. These staff are not involved in analysis or statistical production so there is a separation of duties between data linkers and data analysts.

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2. Coronavirus (COVID-19) Test and Trace data for England

NHS Test and Trace in England was launched on 28 May 2020. The dataset contains record-level data of COVID-19 testing provided by the NHS in England.


The dataset is used for enhancing the Coronavirus Infection Survey (CIS) work, giving the ability to find cases of repeat infections among the CIS participant sample, and improving understanding of the spread and outcomes of the disease. The Test and Trace data are also linked to other health datasets, such as General Practice Extraction Service (GPES) Data for Pandemic Planning and Research (GDPPR) and Death Registrations data, which have been used to answer emerging questions related to COVID-19. Research has included modelling case rates by demographic characteristics, risk of death by variant, and outcomes relating to testing behaviours.

Additional information about ethical scrutiny

The relevant National Statistician's Data Ethics Advisory Committee (NSDEC) minutes for uses of this dataset include NSDEC minutes for November 2020 and January 2021 and NSDEC minutes for March 2022.

Data minimisation

The ONS worked with the UKHSA to agree a data specification that met our needs but limited the data we received to that necessary for statistical production.

Additional information about data protection

The line-level data provided to the ONS shall never leave the ONS Secure Research Service (SRS). Researchers, with approval, can be given access, but they are never allowed to take the data away from the SRS technical platform. Data are provided to the ONS from the Department of Health and Social Care (DHSC) system on the basis that the ONS does not combine data in a way that can identify a data subject other than is necessary to link records to the COVID-19 Infection Survey and/or other such studies where the linking enables necessary scientific research and statistical analysis inquiries. The ONS, upon receiving those data, must make those data anonymised prior to the data’s use by accredited researchers or the UKHSA.

Examples of impact

Test and Trace data have been used to answer emerging questions related to COVID-19 and improve risk factor research. This has provided support for government actions to control the COVID-19 pandemic in England by identifying at-risk population subgroups. Analysis into variants confirmed that Omicron was less severe than Delta, and this information was used to inform the government decision to relax restrictions. Other statistical work was used by GO Science to assess the performance of the Test and Trace system.

Further information

There is more information on NHS Test and Trace on the GOV.UK website.

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3. National Immunisation Management Service (NIMS) for COVID-19 vaccinations

This comprises record-level data of coronavirus (COVID-19) vaccinations provided by the NHS in England. This includes NHS Number and information on the location and administration details of vaccinations.


The Office for National Statistics (ONS) has been asked to provide rapid responses to the coronavirus pandemic on emerging research questions, which are arising as the pandemic continues and as understanding of COVID-19 and its impact increases. This work is to support the ongoing government response and has been requested by central government leaders and advisors such as the Scientific Advisory Group for Emergencies (SAGE), via the National Statistician. The work will improve understanding of and support the development of statistics on:

  • incidence and transmission rates of COVID-19 among different demographic and geographic populations, and the factors associated with differences in such rates
  • the short, medium, and long-term impacts of having had COVID-19, treatment for COVID-19, or a COVID-19 vaccine
  • the coronavirus pandemic and its associated social, economic, and environmental impacts on health and well-being
  • linkage of vaccination data with other data sources already held, building a rich picture of the health state and experiences of the population because of COVID-19
  • linking Coronavirus Infection Survey (CIS) data with vaccination data to better inform policy decisions made on the basis of incidence rates tracked through this study
  • using vaccination data to inform work on COVID-19 risk models
  • data being used to quality assure and validate Census 2021
  • exploring the relationship between employment and health conditions, treatments and service use

Additional information about ethical scrutiny

The relevant National Statistician's Data Ethics Advisory Committee (NSDEC) minutes for uses of this dataset include:

Data minimisation

Only fields that are deemed necessary for the purposes of analysis in line with the ONS' function have been requested. The ONS will make the vaccination data received under this agreement available to approved researchers through the ONS’ Secure Research Service in line with its functions to promote and assist statistical research.

Examples of impact

Linking the ONS census to National Immunisation Management System (NIMS) data enabled the ONS to investigate inequality in the coverage of vaccination against COVID-19, focusing on a range of sociodemographic characteristics, such as ethnicity, religion, disability, and deprivation. ONS publications investigating mortality have also identified groups at risk and those who should receive further boosters. An ONS study showed that populations that are most likely to be disproportionately affected by COVID-19 seemed most hesitant to receive a vaccination. The government was able to adapt policies to improve these disparities. A study investigating vaccination and mortality in young people provided reassurance that the risk of cardiac death in young people was not elevated after vaccination. This was used by the Medicines and Healthcare products Regulatory Agency (MHRA) to inform guidelines.

Further information

Further information on national vaccination programmes is available on the NHS website.

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4. The National Radiotherapy and Systematic Anti-Cancer Therapy (SACT) Datasets

The National Radiotherapy Dataset includes all patients in England recorded in the dataset who received treatment (all types) with radiotherapy between 1 June 2018 and 31 August 2020. 

The SACT dataset includes all patients in England recorded in the dataset who received treatment between 1 June 2018 and 30 June 2020. 

These datasets were supplied by Public Health England (PHE). PHE has since been replaced by the UK Health Security Agency and Office for Health Improvement and Disparities.


The Chief Medical Officer asked the Office for National Statistics (ONS) to quality assure a QCOVID® algorithm developed by Oxford University to identify clinical vulnerability to coronavirus (COVID-19).  

The ONS ran the QCOVID® model against our linked data assets to validate the statistical performance of the QCOVID® algorithm in a dataset that is independent of the dataset used to develop the model. An independent team of experts also undertook the validation, providing the highest level of assurance regarding the performance of the algorithm in line with Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) guidance. 

These data on radiotherapy and chemotherapy were required to add to a larger health data asset, which exists in the ONS, comprising census, hospital episode, and GP data as the basis for this research.

Additional information about QCOVID®

QCOVID® is an evidence-based model that uses a range of factors such as age, sex, ethnicity, and existing medical conditions to predict risk of death or hospitalisation from COVID-19. It provides nuanced information on people’s risk of serious illness due to COVID-19 and has the potential to help patients and doctors reach a shared understanding of risk. It is a “living” risk prediction model, which will be updated regularly as our understanding of COVID-19 increases and more data become available.

Data minimisation

Data were delivered on a one-off basis in November 2020. Only a snapshot of the data was provided, rather than the complete dataset.

Examples of impact

Data were used to independently validate the QCOVID® population-based risk algorithm. This work was successful, showing the model performed well, and demonstrated very high levels of discrimination for COVID-19 deaths in men and women for both time periods. This work provided confidence that the model was robust and met the highest standards of evidence.

Further information 

You can find more information about the National Radiotherapy Dataset on their website. 

You can also find more information about the Systemic Anti-Cancer Therapy Dataset on the NHS website.

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