Assessment of compliance with the Code of Practice for Statistics – 2021 Census in Northern Ireland

17 November 2021
Last updated:
25 July 2022

Executive summary

Why this assessment is needed

The Census is one of the most important sources of data and statistics, informing decisions about almost every aspect of life within the UK. It allows users – including government, local authorities, academics, and commercial businesses – access to important information on the people and households of the UK and helps people get a better understanding of the places in which they live and work.

The Office for Statistics Regulation (OSR) is carrying out assessments of the UK Censuses produced by the Office for National Statistics (ONS), the National Records of Scotland (NRS) and the Northern Ireland Statistics and Research Agency (NISRA). The assessments will allow OSR to recommend whether the Census outputs should be designated as National Statistics, in accordance with the requirements of the Statistics and Registration Service Act 2007, when they are first released.

It is essential that the data and statistics from the Censuses are reliable and provide valuable insights, meeting the rigorous standards of trustworthiness, quality and value outlined in the Code of Practice for Statistics. This assessment report focuses on the 2021 Census in Northern Ireland, produced by NISRA, and aims to identify areas of strength, good practice and innovation in NISRA’s Census planning and development as well as identifying some areas where improvements need to be made.

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What we found

NISRA has successfully delivered Census operations for Northern Ireland during the COVID-19 pandemic, overcoming many challenges to its systems and service delivery. Census return rates in Northern Ireland reflected a high level of participation, with 97 percent of occupied households returning Census questionnaires. The Census team in NISRA has worked flexibly to effectively reprioritise resources and modify its plans for the Census collection period, ensuring live operations were undertaken safely for both the public and NISRA staff. This has been a significant achievement for the core Census team and all involved in operational delivery.

The data from Census 2021 will provide a snapshot of life in Northern Ireland at this unprecedented time. Data collected during this time may well be unusual or changed from what might have been expected, particularly on topics such as employment and economic activity. NISRA now has an important role in understanding and explaining the impacts on the data to users, supporting the appropriate use of Census data, and seeking to address any unmet user needs as a result.

NISRA launched its outputs consultation in October 2021, to gather views from data users and stakeholders on its plans for Census outputs. Consultation events have been arranged to promote and explain its current plans, with both general interest and targeted audience groups. This will be an extremely important exercise to understand the needs of a wide and varied group of users, as NISRA finalises its plans to deliver high quality and valuable Census data and statistics. In its work to improve how Census data will be disseminated to users, NISRA has worked collaboratively with ONS and the Central Statistics Office (CSO) in the Republic of Ireland to utilise new tools which will increase the accessibility and flexibility of Census data. The real value of the 2021 Census in Northern Ireland will be realised when Census data and statistics are released. NISRA is committed to successfully achieving that aim.

As NISRA works to process and produce Census data and statistics for Northern Ireland, it must also continue to prepare its supporting information on quality, data sources, and methods. During the earlier stages in Census planning, limited detailed information was published on NISRA’s research, developments or judgements on quality and methods while these were still being finalised. NISRA should continue its work to ensure that Census outputs are accompanied by finalised information on quality to support users and assure them on the data sources and methods used in their preparation.

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We have identified several ways NISRA needs to implement improvements to support appropriate use of the data and meet users’ needs to comply with the highest standards of the Code.

NISRA has made little information widely available on the steps it is taking to investigate, or otherwise meet, user needs for data affected by COVID-19. This is a significant gap in the assurances offered by NISRA on its plans to address impacts on data.

Requirement 1

In order to support society’s need for information, NISRA needs to clearly communicate how 2021 Census data may be impacted by COVID-19 and how it plans to address any unmet user needs. NISRA should ensure this information is communicated in an accessible and timely way, being open on plans, developments and progress even where definitive answers or solutions are still being sought.

Further steps need to be taken by NISRA to communicate plans and provide more-detailed information, when available, to users of UK population estimates, UK Census data and Ireland-Northern Ireland outputs. As the provision of UK data and statistics is the responsibility of ONS, NISRA should signpost users to related ONS materials on the UK population estimates and UK Census data as this becomes available.

Requirement 2

To assure Northern Ireland users of how their data needs will be addressed, NISRA needs to provide users with transparent, accessible and timely information on how UK population estimates for 2021, UK Census data and Ireland-Northern Ireland data will be provided. NISRA should continue to work with, and align communications with, ONS, NRS and CSO to explain any impacts on data quality and describe where user needs may or may not be met as a result.

To assure users of the value and quality of Census data, NISRA should ensure its plans to provide information on quality – including information on data collection and processing, quality assurance activities and quality measures, methods and use of administrative data, and NISRA’s judgement on appropriate use of Census data – are delivered as planned.

Requirement 3

NISRA should ensure finalised documentation on quality, information and judgements on suitable data sources, and methods and their application are complete. All supporting information should be sufficiently open and easily available to Census data users alongside its range of Census outputs.

With such a wide and varied set of users of Census data, NISRA needs to engage with user groups with different requirements and interests. This includes special interest groups or those from a topic-focussed perspective or when, for example, considering the needs of users with different levels of expertise or accessibility requirements.

Requirement 4

In order to ensure the relevance of data and statistics to users, NISRA needs to continue to develop and enhance its user engagement activities, connecting with a broad range of users and embracing challenge. NISRA should continually review and seek to implement improvements in its engagement strategies and should ensure its decision making is open and transparent, being clear where users’ needs can or cannot be met.

NISRA aims for a first release of Census Population and Household estimates by summer 2022, with all other planned Census releases being published by summer 2023. NISRA is also committed to producing Census outputs that meet users’ needs and that are timely, accessible and flexible. Producing timely and accurate data from the Census is vital to ensuring high public value.

Requirement 5

NISRA needs to deliver its aims in relation to timely, accessible and flexible Census outputs – while ensuring sufficient data quality and supporting appropriate use of the data. It should clearly communicate its plans and timelines for outputs at the earliest opportunity, updating and revising these as soon as more detail is available or to reflect any changes to its plans.

Having accessible and easily findable information supports the appropriate use of data and statistics.

Requirement 6

To best support Census data users, NISRA needs to continue to improve its webpage navigation for current materials. NISRA’s plans for a separate website or webpages for Census outputs themselves will require sufficient consideration of its navigation and accessibility. NISRA should keep webpages and content refreshed and current.

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Judgement on National Statistics Status

We have identified six requirements for NISRA to address in order to ensure the high standards of public value, quality and trustworthiness associated with National Statistics designation are met.

Once NISRA has demonstrated that the improvements covered by these requirements have been made or provided sufficient assurance that our expectation for the data and statistics will be met, OSR will recommend to the UK Statistics Authority that National Statistics status for these statistics be confirmed. NISRA is aiming to meet the requirements of this report by spring 2022 so a designation decision can be made ahead of first Census outputs in summer 2022.

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