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The following provides further information on the data sources and terminology used.

First published:
19 February 2019
Last updated:

Source and sample size

These figures are based on results from the Annual Population Survey (APS) which samples around 18,000 households in Wales every year. However, the sample sizes for people identifying as gay, lesbian or bisexual are relatively small and hence we have also produced analysis from a pooled dataset which combines 3 years of APS data.

Sexual identity estimates were previously produced from the Integrated Household Survey (IHS). IHS variables (including sexual identity) were added to the APS in 2014 and fully integrated into the survey in 2015.


As part of their ‘Sexual orientation, UK: 2018’ release, the Office for National Statistics published revisions to the series of estimates for the years 2014 to 2017. Further details of the revisions made to the data and their impact are outlined in the bulletin.

Estimates for the years 2012 and 2013 were not revised. A comparable time series of estimates is therefore now available back to 2014.

The impact of these revisions on headline figures for Wales was minimal. However, previously published sexual identity estimates for Wales have been revised in accordance with the Welsh Government’s statistical revisions policy.

Sexual identity or sexual orientation?

Sexual orientation is an umbrella term which encompasses several dimensions including sexual identity, attraction and behaviour.

The APS collects information on self-perceived sexual identity from the UK household population aged 16 years and over. Self-perceived sexual identity is a subjective view of oneself. Essentially, it is about how a person views themselves, not what they do. It is about the inner sense of self, and perhaps sharing a collective social identity with a group of other people.

The APS question on sexual identity is asked as an opinion question, it is up to respondents to decide how they define themselves in relation to the four response categories available. It is important to recognise that the question is not specifically about sexual behaviour or attraction, which are separate concepts not currently measured by the APS. However, these aspects might relate to the formation of identity. A person can have a sexual identity while not being sexually active. The "Other" option on the question is included to address the fact that not all people will consider they fall in the first three categories, that is, heterosexual or straight, gay or lesbian or bisexual.

The question is asked of respondents aged 16 years and over; it is not asked by proxy. Proxy interviews are defined as those where answers are supplied by a third party, who is usually a member of the respondent’s household.

Further information

The Office for National Statistics has recommended a new voluntary question on sexual orientation for those aged 16 years and over for the England and Wales 2021 Census. The data gathered will make it easier to monitor inequalities under the anti-discrimination duties of the Equality Act 2010 and allow charities, local and central government to effectively target services intended for the lesbian, gay and bisexual (LGB) community. For more information, see the Government white paper which was published in December 2018.

Scott Clifford

Telephone: 0300 025 3234


Telephone: 0300 025 8099