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Data collection methodology (DCM)

Optimising information gathered by surveys.

What is data collection?

Data collection is simply how information is gathered. There are various methods of data collection, such as personal interviewing, telephone, mail and the internet. Depending on the survey design, these methods can be used separately or combined.

The DCM team advises on data collection methods for all ONS social and business surveys and the census.

With clients both within ONS and the wider government community, we aim to provide expert advice on data collection procedures and carry out research leading to improvements in survey quality.

DCM advises on a diverse range of surveys. To do this, the team assesses the various survey processes at the data collection stage.


DCM contributes to the development of a common statistical infrastructure for ONS. The team aims to provide business areas with methodological standards and expert advice on procedures to minimise error, in order to produce accurate survey estimates and thereby maintain the quality of data output.

DCM is also involved in ongoing research to assess and improve methods of data collection and in developing new ways of collecting data, for example, via the web.

Current and planned areas of work

The main work we do involves giving advice, support and methodological expertise in the following areas:

  • standards and principles of designing, testing, evaluating and implementing survey processes at the data collection stage

  • expert reviews of questionnaires/data collection instruments

  • cognitive question testing to develop questions for surveys

  • moderation of focus groups to discuss survey topics and concepts

  • measurement and reduction of non-response error

  • implementation of standard response outcome codes

  • methods of calculating response rates

  • methods of identifying key responders for priority response chasing

  • coding and social classification for surveys

  • new and improved methods of data collection

For further details on services and publications, visit the DCM's services and publications pages.

Contact data collection methodology

Please contact us for further information about how Data Collection Methodology (DCM) could help you with the development, testing and evaluation of survey questionnaires or with qualitative studies:


The methodology and quality pages provide information about other aspects of survey methodology.

For information not related to DCM's specific services, please contact the ONS customer contact centre.

Content from the Office for National Statistics.
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