Dear Jen

Update on the Review of 2021 England and Wales Census data on Gender Identity

I wrote to you in April 2023 about our decision to undertake a short review of statistics on gender identity based on data collected as part of the 2021 England and Wales Census. This was in part a response to the media coverage of the publication of these data.

I am writing to welcome the article published today by the Office for National Statistics (ONS) on collecting and processing data on gender identity, England and Wales: Census 2021, , and its commitment to publishing further information providing greater insight into the data. This is a positive first step in addressing user need on this topic and we recognise the volume of work being undertaken at pace to develop these articles.

As you know, our review is examining the approach taken by ONS in responding to questions raised by users about the results of the gender identity data to form a judgement as to whether this aligns with the expectations set out in the Code of Practice for Statistics. Your team has been proactive in sharing updates on the development of these articles with OSR to inform our review. This has been extremely appreciated and useful for informing the research and engagement we’ve undertaken.

While our review has not yet concluded, I would like to share some of the emerging findings with you that we will provide more detail on in our report. We have found examples of positive behaviours in line with the Code:

  • In general, more topic-based quality assurance was carried out for Census 2021 than in previous years. Gender identity and sexual orientation was one of 13 topics assigned for bespoke quality assurance reports. The team carrying out the quality assurance worked closely with the relevant topic leads in ONS, to apply expert insight to the data to test thinking. These quality assurance reports then went through an independent quality assurance panel, comprising of experienced researchers, to apply additional scrutiny to the data.
  • We are encouraged by how open and reflective the team leading the quality assurance has been throughout our engagement. The team told us it analysed relationships between the gender identity data and other variables based on areas that were of public interest at the time. It agreed that, with more time to look at all combinations of variables, for example looking at gender identity and ethnicity, it may have identified areas for additional probing and analysis.
  • When ONS began receiving queries on this topic, it set up triage meetings that allowed the relevant teams across the organisation to join up and share their perspective on the queries, to provide coordinated and coherent responses to users. This also enabled ONS to respond to media enquiries more easily.

These are novel data, and we recognise that ONS’ approach to releasing data has been made in the spirit of transparency and providing insight on topics of high public interest. There are some lessons learned and opportunities that have emerged from our review so far, that could enhance the trustworthiness, quality and value of these statistics.

  • When releasing big data sets for the first time, it is inevitable that users will want to interrogate and analyse the data for their own purposes. ONS could have done more to see this as an opportunity to crowd source quality assurance, or at a minimum, be clearer that it was open to feedback as part of releasing the data. ONS should consider having relevant policies in place to manage this type of user input in future releases.
  • The communication of uncertainty should be strengthened. Users told us that they would like to see ONS include more caveats alongside the data and expand the quality information to set out how the data can and can’t be used. Although ONS has assured itself that the data appear to triangulate with other sources at the national level, there is a need to communicate the uncertainty of more granular breakdowns to support appropriate use of the data. For some users, the national level comparisons will be sufficient, but ONS should consider how it supports the onward use of the granular breakdowns.

The further research that ONS has committed to publishing in Summer 2023 is essential to ensure trust in these statistics. We look forward to the publication of these remaining articles and OSR will publish its full findings after we have reviewed, and engaged with users on, the full set of articles.

Yours sincerely

Ed Humpherson
Director General for Regulation


Related Links:

Ed Humpherson to Jen Woolford: Statistics on Gender Identity based on the 2021 England and Wales Census data