Data quality index for census geographies

The data quality index for census geographies is available at the following geographical levels: provinces and territories, census divisions, census subdivisions, census tracts, dissemination areas, federal electoral districts, forward sortation areas, census agglomerations and census metropolitan areas, urban areas, designated places, dissemination blocks and dissolved census subdivisions.

In general, the census has been able to obtain accurate population and dwelling counts and to maintain high response rates to census questions for all geographic areas in Canada. However, some census subdivisions (CSDs), mostly Indian reserves and Indian settlements, have registered very high non-response rates for some census questions. A data quality index based on a global non response rate is calculated for all the above geographies to reflect the level of quality. The global non-response rate is the percentage of required responses left unanswered by the respondents. Only census questions intended for dissemination purposes are used in the calculation of the global non-response rate.

Geographical areas with no data quality index shown have a global non-response rate lower than 5%. Tabulations for which the data quality index is greater than or equal to 5% but less than 25% are to be used with caution. Only population and dwelling counts are released for the geographical areas for which the data quality index is greater than or equal to 25%. This non response is a very localized phenomenon; hence census data other than population and dwelling counts are included in all higher geographic level tabulations. Tabulations for all geographical areas containing one or more of these suppressed areas are not subject to any particular note unless the higher level geography registers a high global non-response rate. Place-of-work tabulations for areas for which the data quality index is greater than or equal to 25% are not released if the majority of the population of these areas both live and work in the same area.

In the 2006 Census, improvements were made in the method of imputing respondent characteristics for individuals in dwellings whose status changed, as a result of the Dwelling Classification Survey, to 'occupied' after being originally classified as 'unoccupied'. As a result of these improvements, for the first time, these imputed responses are included in the data quality index calculation. In previous censuses, the non-response component due to unoccupied dwellings reclassified as occupied was accounted for through adjustments to the weights of responding households and, as such, was not considered in the data quality index. At the national level, the non-response related to the unoccupied dwellings accounts for approximately 16% of the global non-response used to determine the data quality index. This contribution will vary geographically as well as according to the size of the geographies.

Note: Lists showing geographical areas with global non-response rates greater than or equal to 5% but less than 25% are available on request, as well as lists showing geographical areas with global non-response rates greater than or equal to 25%. A list showing CSDs of work with a global non response rate greater than or equal to 25%, if the majority of the population of these CSDs both live and work in the same area, is also available.