1991 Household SAR

The 1991 Household SAR is a one per cent sample of households and all individuals in those households. It is a hierarchical file allowing linkages between individuals. The geographical base of the 1991 Household SAR is the Registrar General's Standard Regions. The SouthEast is split into Inner and Outer London and the remainder of the SouthEast. The SARs were drawn from the fully coded set of census records returned by households and institutions. They therefore omit wholly imputed households and also households that were missed by the census.

The 1991 Household SAR also contains about 40 variables, similar to those in the Individual file. However, the structure of the file allows a large number of other variables to be derived. Many new variables have been created for the hierarchical household file since summary information about a household can be computed from data about the individuals in that household.

Both 1991 SARs were selected from the 10% sample of the 1991 Census. The 1991 Household SAR was selected first. Households were ordered geographically by county and enumeration district in England and Wales, by region and output area in Scotland. They were then grouped into ten households at a time and one household was selected at random from each group. The sampled records were then scrambled to prevent geographical tracing within a SAR area.

The 1991 Household SAR approximates to a simple stratified random sample of households, although counts of individuals in the household file are subject to the effects of clustering.