Census microdata comprise information on individuals' responses to the UK Census. Microdata samples are available for individual and household records from the 1991 and 2001 Censuses. The samples are anonymised, contain no identifiers and the data treated so as protect respondents' confidentiality.

Treatments include:

  • supplying only a small sample of records (5% or less)

  • restricting the variables supplied and collapsing categories within the variables

  • perturbing unusual combinations of variables for some individuals or households

  • supplying only high level geography information

It is therefore neither possible to identify any individual or household from the data, nor possible to disclose any information on any individual or household, using these samples.

The samples are only suitable for statistical research purposes. Users may wish to use the Samples of Anonymised Records (SARs) to customise their own output, where a specific combination of variables is not available in standard census outputs. The samples are also suitable for performing multivariate statistical analysis.

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