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Introduction to Harmonisation


The UK has a wide range of government surveys that provide sources of social and economic information. The Census of Population is the largest and best known, but there are many others covering topics such as economic activity, income, expenditure, food, health, education, housing and transport. Most of these are continuous household surveys. Others, covering topics such as crime, dental health and house condition, are repeated regularly. The government also commissions single surveys from time to time on subjects of national importance, such as the prevalence of disability and mental ill-health.

These surveys were designed at different times, to meet different needs, and have been commissioned by a range of departments. Consequently, the surveys were developed mostly in isolation from each other. This resulted in a lack of cohesion. Differences arose in concepts, definitions, design, fieldwork and processing practices, or “inputs”, and also in the way results are released, or “outputs”. This lack of cohesion was a source of frustration for many users.

A major factor behind the creation of National Statistics in 1996 was the desire to improve the service being provided to users of statistics, and the availability and accessibility of those statistics. A cross-governmental programme of work is looking into standardising inputs and outputs. This is known as harmonisation and the Office for National Statistics leads this programme of work. The aim is to make it easier for users to draw clearer and more robust comparisons between data sources.

This work is monitored by the Government Statistical Service (GSS) through the National Statistics Harmonisation Group (NSHG), who are responsible for development and maintenance of common statistical frames, definitions, questions and classifications for statistics. The NSHG feeds into the GSS Statistical Policy and Standards Committee (GSS SPSC), responsible for the agreement and promotion of statistical policies and standards covering all Official Statistics managed by the GSS.

NSHG Topic Groups, led by a subject matter expert, have been established to develop, review and maintain the harmonised principles used throughout the majority of government social surveys. The current NSHG Topic Groups are:

Benefits and Tax Credits
Consumer Durables
Country of Birth, Migration and Citizenship
Crime and Anti-social Behaviour
Demographic Information
Economic Activity
Ethnicity, Identity, Language and Religion
Health, Disability and Carers
Housing and Tenure

For more information, please contact the Harmonisation Team:

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