National Study of Health and Relationships (Natsal)

Version 3

Last updated: 28/04/2023

Who is doing the research?

This study is being carried out by NatCen Social Research (NatCen), University College London (UCL), the London School of Hygiene and Tropical Medicine (LSHTM), the University of Glasgow and Örebro University Hospital, Sweden. The study is funded through the Wellcome Trust, Economic and Social Research Council and the National Institute for Health Research.

What is the study about?

This is a study on health and relationships in Britain and is one of the largest studies of its kind in the world. The study is sometimes also called Natsal – the National Survey of Sexual Attitudes and Lifestyles. It has taken place every 10 years since 1990 and the findings have been widely used by doctors, health service providers, policy makers and scientists to help plan health services and health education programmes. The last survey was in 2010, and we now need updated information to understand how attitudes and lifestyles have changed.

Do I have to take part?

Taking part is voluntary and if you do decide to take part, you can choose to answer as many or as few questions as you like. You can withdraw your consent at any point in time by contacting NatCen using the details below.

What is the legal basis for processing this data?

The Joint Data Controllers for Natsal are NatCen, UCL, LSHTM, the University of Glasgow and Örebro University Hospital, Sweden. NatCen is the responsible point of contact and will collect the survey data for the study.

The lawful basis NatCen relies on to process your data is legitimate interest. The lawful basis relied on by the academic collaborators to process your data is performance of a task in the public interest. The lawful basis for processing special category data is for the purpose of archiving, research and statistics.

What will happen to any information I give?

Any information given will be treated in confidence and we will handle your data in accordance with the Data Protection Act 2018 and the UK General Data Protection Regulation (GDPR). The survey findings will be anonymised and nothing we publish will identify you or your household.

Personal identifiers that can be used to identify you (such as your name and address) will be stored separately from your survey answers. Personal identifiers will not be shared outside NatCen, unless you agreed to have your survey answers linked to other datasets or if you agree to be contacted about future research studies.

We will create a dataset that combines your data with the information collected from other people who take part in the study. The dataset will not include information which could directly identify you. This de-identified data will only be used for activities that have the potential to benefit wider society (e.g. research, education, policy making, public engagement). No statistics or findings will be released in a way that could identify an individual.

Occasionally, people who take part in Natsal might tell us things that raise concerns about their safety or the safety of others. If this happens, we may need to investigate this further as part of our ethical duty.

Linking survey answers to other information?

We will ask for your consent to link your survey answers to other datasets about your health, education, and administrative and survey datasets held by the Office for National Statistics (ONS).

If you agree, NatCen will securely transfer your personal details (name, address, sex and date of birth) to the organisations that hold your health, education and other administrative records. These can be NHS organisations and government departments in the UK, and also University and Statistics Authorities which are tasked with the secure use of records in research.

Once your records have been identified your personal details will be removed and replaced with a unique study identifier. This will then allow the organisations holding your administrative records to make a copy of the relevant parts of your record. These will then be combined with your survey answers and transferred to a secure research server, which enables secure storage, handling and analysing of data under restricted access arrangements.

The linked data will be used for research and statistical purposes only, by approved professional, academic and social policy researchers. Access to the data by these researchers will only be granted through a separate written application and training process. This ensures that the data is used responsibly and safely. Permission will only be given to researchers who can explain the potential impact of the research and its wider value for society.

Names and addresses will never be included in the research dataset, nor any published results, and so no individual will be identifiable from the research.

Recontact for future studies

In the future, we may contact you to invite you to take part in another related research study. We will only do this if you gave consent to this during your Natsal interview. If we contact you in the future, you will be able to decide whether you want to participate in that research study at the time. If you want to remove your consent to be re-contacted for future studies, you can contact NatCen using the contact details below.

What happens to my biological samples?

If you give a biological sample, we will test this in a certified laboratory for some infections that can be transmitted through sexual activity, as well as other microbes that are harmless and live in the genital tract. The tests do not involve human DNA or human genetic analysis. Sample collection and storage is controlled by the Human Tissue Act (2004). The laboratory will not know your name or address. The data will be kept strictly confidential, and no results will ever be traced to you or given to you.

Samples will be sent to certified laboratories including The Doctors Laboratory (TDL) and the UK Health Security Agency (UKHSA - previously part of Public Health England). The samples may be sent to Natsal Investigators and collaborators, including at the World Health Organization STI Reference centre in Sweden and the Wellcome Sanger Institute in the UK.

We will ask you separately for consent to store what is left over from your sample after the initial tests have been done. If you agree, any remaining sample may be used for future studies, for example, when new tests become available. The tests will never involve analysis of human DNA or genetics. Stored samples will only be used for future studies if all necessary approvals and permissions have been obtained in advance. The sample will not be labelled with your identifying information.

How long will you keep my data?

Natsal gives us very important information about how people’s health and relationships have changed over time. To help us do this, we would like to keep information about people’s health and relationships, so we can look at trends over time. If you give permission for us to store any remaining biological sample, it will be stored until it is used in future research studies. Due to the nature of research, we are unable to set any particular time limit on the retention of your survey data and samples, but we will keep it under regular review and ensure that neither are kept longer than is necessary. 

We will only retain personal identifiers and biological samples to support the research project and findings. If you do not consent to: (1) linking your survey answers to other information, (2) recontact for future studies, and (3) biological sample storage, then we will delete your name and address within 12 months of the end of the study. If you do not consent to the storage of biological samples, we will destroy any samples you give within 12 months of the end of the study.

What if I change my mind?

You can withdraw your consent to participate in the study at any point in time by contacting NatCen using the details below. We will remove data about you that is personally identifiable (e.g. contains information such as your name, address), but we will not remove data from de-personalised datasets. For biological samples, NatCen will inform the relevant laboratories and the sample will be destroyed.

Where is my data stored?

NatCen will securely store your data, including personal identifiers, in line with ISO27001, ISO 20252 and Cyber Essentials Plus certification.

The de-identified data will be held as a resource for use by professional, academic and social policy researchers for research, educational and statistical purposes only. This dataset will be held on a secure research server, which enables secure storage, handling and analysing of data under restricted access arrangements.

Together with the previous Natsal survey datasets, a copy of the de-identified data will be securely deposited in the UK Data Archive, which is based at the University of Essex and operates under a licencing agreement. Researchers can register with the UK Data Archive to access Natsal data, which can only be used for genuine research for public interest and never for commercial gain.

Who can I contact?

For more information about the study you can visit

If you have any queries, or want to request that we change or delete your information, please contact NatCen on; Freephone 0800 452 4568 or NatCen Social Research, Kings House, 101-135 Kings Road, Brentwood, Essex, CM14 4LX.

You can contact the NatCen Data Protection Officer by email at To read our data protection policy, visit Data Protection Officers are responsible for upholding your rights and making sure we process your information correctly.

If you have a complaint, please get in touch by contacting NatCen on or Freephone 0800 452 4568. You also have the right to lodge a complaint with the Information Commissioner’s Office at: Information Commissioner’s Office, Wycliffe House, Water Lane, Wilmslow, SK9 5AF, telephone 0303 123 1113, email:, website:

UCL’s General Privacy Notice can be found here.