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What are classifications and standards?

This page answers common questions about statistical classifications and standards.

What is a classification?

Generally a statistical classification is a way to group a set of related categories in a meaningful, systematic, and standard format. The statistical classification is usually exhaustive, has mutually exclusive and well-described categories, and has either a hierarchical or a flat structure. A statistical classification usually contains codes and descriptors.

Why have a classification?

Classifications allow us to group and organise information meaningfully and systematically, usually in exhaustive and structured sets of categories. Statistical classifications are generally developed to support policymaking and because of that, to organise and present statistics. A primary purpose of a statistical classification is to provide a simplification of the real world and a useful framework for collecting and analysing data from both statistical and administrative collections.

What is a statistical standard?

A statistical standard provides a comprehensive set of guidelines for surveys and administrative sources collecting information on a particular topic. Components of a standard include:

  • rationale 
  • definition 
  • classification and coding process 
  • questionnaire module
  • output 
  • related classifications and standards
  • glossary and references.

Why have statistical standards?

Statistical standards allow us to collect reliable statistics using consistent procedures. If we follow these standards, we can integrate data over time and across different data sources, allowing data to be used beyond the immediate purpose for which it was produced. Statistical standards also reduce the resources required to develop and maintain surveys.

What is coding?

Coding is the process by which a description of an item or activity supplied as a survey response is matched to a coded category. The coded categories are defined in standard classifications.

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