open menu

The Administrative Data Research Network is an ESRC-funded project that ran from October 2013 - July 2018. It is currently at the end of its funding cycle and is no longer taking applications. Administrative data research will be taken forward in a new project, to be launched later in 2018.

Exploring differences in the reporting of Welsh language ability:  An exploratory study linking survey and Census data

Research Overview

The project, led by Martin Parry, a Senior Welsh Language Officer at the Welsh Government, will use data from the UK Census and the National Survey for Wales (NSW) – the first time the two sources of information have been linked in this way.                                                                                     

The Welsh Government is committed to supporting the Welsh language, and wants to see a million people speaking Welsh by 2020. The figure currently stands at over 560,000, according to the 2011 Census.



Census estimates of Welsh language ability are traditionally lower than estimates from other national surveys, such as the NSW. The idea of this research is to get a better understanding of how people answer questions about their ability in the Welsh language.

Increasing the numbers of Welsh speakers is an important priority for Welsh Government and to achieve that, they need to assess the situation as it stands now, and set objectives based on the evidence. This project will be a huge boost to that evidence, and help to produce informed policy, which could make sure the Welsh language and Welsh culture remain vibrant for future generations.

The research also has implications for the Census Transformation Programme, which aims to make recommendations for modernising the Census in future by using more administrative data. Understanding the different sources on the Welsh language will contribute to that – and changing the Census has potentially huge benefits for society, value for money and the UK’s statistical infrastructure.


Government departments

 Welsh Government

More about the research

The findings of the research will be presented to policy officials in the Welsh Government and other stakeholders such as Welsh language researchers, and others involved in statistics, especially household surveys.

The research was made possible by an agreement between the UK’s Office for National Statistics, the Welsh Government and the Administrative Data Research Centre Wales. They devised a way to link Census data, which is not normally allowed to leave ONS, and Welsh National Survey data, which has to remain in the NHS Wales Informatics Service/Secure Anonymised Information Linkage (SAIL) Databank in Swansea. They did this in such a way that the identities of people whose data was involved were kept safe, and could not be seen by researchers.

Date approved

September 2016

Research team/lead researcher

Martin Parry

Page last updated: 24/10/2017