Microdata are small samples of data for whole households and individuals, which include some associated census characteristics but no information that could identify a household or individual.

Microdata products enable researchers to look at combinations of characteristics that are not generally available from the standard census tables, and to perform different types of analyses not possible from standard tabulations.

National Records of Scotland (NRS) is committed to making data available as widely as possible and is responsible for maximising the benefits from Scotland’s Census 2011. As part of this it has released several different microdata products which seek to strike a balance between detail and security, allowing a flexible tool set for casual users as well as professional researchers.  Three levels of microdata have been released for the 2011 Census:

Microdata Teaching File

This file contains anonymised records on a limited set of variables for a random sample of 1 per cent of people in the 2011 Census output database for Scotland.

Secure Microdata Files

The secure microdata files consist of random samples of 10 per cent of people and 10 per cent of households in the 2011 Census output database for Scotland.

Safeguarded Microdata Files

The safeguarded microdata files consist of two random samples, each of 5 per cent of people in the 2011 Census output database for Scotland.

Microdata samples from previous censuses (1961, 1971, 1981, 1991 and 2001) are also available at the UK Data Service and in the ONS’s Secure Research Service (formerly known as the Virtual Microdata Laboratory (VML)).