Sex and gender harmonisation guidance

Policy details

This page provides information on work that is currently taking place across the Government Statistical Service (GSS) to harmonise measures of sex and gender in data collection across government. We recognise that sex and gender are distinct concepts but as they are closely related, they are presented together on this page.

For more information or advice on this topic, please contact Harmonisation@statistics.gov.uk.

What we mean by harmonisation

Harmonisation is the process of making statistics and data more comparable, consistent and coherent. The GSS Harmonisation Team works across the UK to promote and facilitate harmonisation.

Measuring sex in the UK censuses

The census in England and Wales is run by the Office for National Statistics (ONS). The National Records of Scotland (NRS) run the census in Scotland and the Northern Ireland Statistics and Research Agency (NISRA) run the census in Northern Ireland.

ONS, NRS, and NISRA have been working closely together throughout development of the 2021 and 2022 Census questionnaires to share research and work towards harmonisation where possible. You can find out more about the work to develop the census questionnaires and improve harmonisation on the ONS website.

The sex data collected in the UK censuses is important because other data analysis is often adjusted to match the proportions of the sexes found in the census. This is important data for understanding population dynamics and projecting future change.

The data gathered on sex in the three censuses is harmonised across the UK.

About the census question on sex

The question “What is your sex?” was asked in:

• the 2011 Census in England, Wales, and Northern Ireland
• Census 2021 in England, Wales, and Northern Ireland
• Scotland’s Census 2022

The response options for each of the censuses where this question was asked were “Female” and “Male”. This question on sex has been asked on the censuses for many decades and the consistency of this is unchanged, which is vital for identifying trends over time.

ONS, NRS, and NISRA have engaged widely with users and stakeholders on the 2021 and 2022 censuses and thoroughly tested their proposals to ensure high quality and consistent data.

Related work

Several pieces of work on the topic of sex and gender are underway across the UK. The teams working on all these projects are communicating regularly with one another to share research and coordinate where possible.

UK census gender identity question

Census 2021 in England and Wales asked a voluntary gender identity question for the first time. You can find details about the voluntary gender identity question from Census 2021 on the ONS website.

Scotland’s Census 2022 asked a voluntary question about trans status and history. You can find details about the voluntary trans status and history question on the Scotland’s Census 2022 website.

NISRA did not ask a question on gender identity in Census 2021 in Northern Ireland because there was a limited user need for a question on gender identity.

Scottish Government working group on sex, gender and data

The Scottish Government have established a working group on sex, gender and data. You can find out more about the Scottish Government working group on the Scottish Government website. The group is led by the Scottish Government’s Chief Statistician and members are professionals from across statistical services. The group considers the guidance that should be offered to public bodies on the collection of data on sex and gender. This includes advice on which form of data collection and disaggregation is most appropriate in different circumstances.

NHS England Unified Information Standard for Protected Characteristics Scoping Project

NHS England are currently carrying out an equality monitoring scoping project to assess the need for a unified information standard for the nine characteristics protected under the Equalities Act (2010). These include sex, gender reassignment, and sexual orientation. This work is currently ongoing. The ONS is a member of the Publication Steering Group for the project and aims to ensure that the approach considers developments across government.

Further information

Inclusive Data Taskforce and GSS Harmonisation Workplan

In October 2020, the National Statistician established the Inclusive Data Taskforce. It was designed to improve the UK’s inclusive data holdings in a broad range of areas. This includes the nine protected characteristics of the Equality Act.

The Taskforce published their recommendations in September 2021. You can read the Taskforce recommendations on the UK Statistics Authority (UKSA) website. Some of the recommendations specifically refer to harmonisation.

In response to the recommendations, the Office for National Statistics (ONS) oversaw the publication of an Implementation Plan in January 2022. You can access the implementation plan for the Taskforce recommendations on the UKSA website. The implementation plan gives information about the current and planned initiatives across the UK statistical system. It refers to a GSS Harmonisation workplan, which was published in February 2022 and recently updated with our current plans. The workplan includes reviewing, refining, and updating harmonised standards. You can access the GSS Harmonisation workplan on the Guidance Hub.

The workplan sets out activities related to the topics of sex and gender identity.

Our future work on the topic of sex will include:

• updating our sex harmonisation guidance by early 2023 to reflect a suite of existing technical guidance for data collectors
• monitoring and reviewing how the current sex question is working
• publishing guidance for telephone and face to face interviewer modes
• undertaking stakeholder engagement – this includes a survey for data users exploring administrative data to better understand how data is collected in administrative datasets for sex

Timescales for this work will be guided by the feedback the team gets throughout the project. We are now working to:

• update our sex harmonisation guidance by early 2023 to reflect a suite of existing technical guidance for data collectors
• publish guidance for telephone and face to face interviewer modes in Summer 2023

You can find more information about our plans for guidance about gender identity in the recently published review of the gender identity data harmonised standard.

Contact us

If you would like to be involved with this work, please contact us at Harmonisation@statistics.gov.uk.

Updates