Getting methodological advice

The Government Statistical Service (GSS) provides access to independent methodological advice with the Methodology Advisory Service (MAS). You can get advice about official statistics, data, and analysis. In most cases this advice is free.

About the Methodology Advisory Service (MAS)

The Methodology Advisory Service (MAS) provides producers of official statistics and statistical research with independent methodological advice and reviews of:

  • data
  • analysis
  • official statistics

This support is given by a team of statistical experts in the Office for National Statistics (ONS).

We work with your own statisticians or analysts, to help develop your work through change and improved understanding. This means that we can concentrate on giving specialist advice that is not widely available.

MAS is managed by the Methodology and Quality Directorate in the ONS.

Areas covered by the Methodology Advisory Service

MAS can advise on all parts of the methodology of producing official statistics and statistical research. It covers a range of topics such as:

  • Analysis Methods
  • Data Science
  • Data Collection Methods
  • Demographic Methods
  • Disclosure Control
  • Index Numbers
  • Matching and Linking
  • Population Estimation
  • Sample Design and Estimation
  • Small Area Estimation

Contact the Methodology Advisory Service

You can contact MAS by emailing us at Please give as much information about your query as possible in your email.

MAS will assess each case and decide on the best way to support your project. MAS will accept cases depending on how complex they are, and whether there are suitable advisors available to help. Because the service is usually free, we do not expect to offer support over more than 5 days.

If you have a query on the content of this page, please email

The Government Statistical Service Methodology Advisory Committee (GSS MAC) was replaced by the Methodology Advisory Service (MAS). You can find the GSS MAC meeting documentation from before 2016 on the National Archive website.