Methodology information for Office for National Statistics outputs
Quality, Methodology and Information (QMI) reports
If you are looking for the QMI report for a particular output there is a searchable store on the Office for National Statistics (ONS) website. These give details of the methodology used and links to quality measures.
Methodology for specific outputs
This page links to content which outlines the methodology for particular outputs.
We will endeavour to keep this up to date. We will add to this when users ask us about this information, however, we cannot include all outputs.
The population and housing census is carried out every ten years by ONS. It collects information about the entire population, and provides detailed statistics down to small area level. The results are freely available and is used across government, industry and society to help answer all sorts of needs.
The census is a complex statistical process, involving many methods. The links below provide information about how past censuses were undertaken and the next census to be held in 2021.
2001 Census
Post-2001 Census Local Authority, Manchester and Westminster studies
2011 Census
2011 Census Coverage Assessment Methods
2021 Census
2021 Census Statistical Design
A Census Methodological Assurance review panel has been set up to provide external, independent assurance and guidance on the statistical methodology underpinning 2021 Census estimates. The papers presented to the Census Methodological Assurance panel are published following each meeting.
Last updated: January 2021