Dear Ian


I am writing to endorse the approach taken by the Department for Transport in producing statistics on the change in transport use during the COVID-19 outbreak. I would like to congratulate everyone involved for their hard work to produce these timely and valuable statistics under extremely challenging circumstances.

These statistics are currently published at the discretion of the Cabinet Office for the government’s daily media briefings. Although the full data series is ultimately made available, it is released on some days and not others. Given their public value, the Department for Transport should commit publicly to a pre-announced release schedule. Doing so should give ample time for the Cabinet Office to decide what and how to present in the daily media briefings and would demonstrate trustworthiness.

My team has conducted a rapid review of these statistics. We have reviewed the extent to which these statistics have been produced in accordance with the Code of Practice’s Trustworthiness, Quality and Value pillars, while taking account of the pressures on you and your teams to deliver near-to real-time statistics about a rapidly changing situation. A summary of our findings and recommendations is set out below.


  • We welcome the rapid development of these statistics and endorse your approach of adapting existing National Statistics data sources in combination with operational data. These statistics are used by the Cabinet Office to show the change in transport trends across Great Britain and give an indication of compliance with social distancing rules. They are vital for informing the government, the media and the general public and will continue to be valuable as the lockdown rules change and we enter the restart and recovery phase of the pandemic. We acknowledge the close engagement that your statisticians have on a regular basis with the Cabinet Office to ensure that the data are well understood. We also acknowledge and encourage your commitment to keep the statistics under review as the demand for new insights changes over the coming weeks and months.


  • The production of these statistics involves a coordinated and considerable effort across multiple analytical teams, overseen by yourself as Head of Profession for Statistics. Clear lines of accountability and responsibility have been established and resources have been reprioritised quickly to enable people to work on this. These measures contribute to demonstrating trustworthiness in the statistics.
  • However, these statistics are currently being released by the Cabinet Office if the information is included in the slides used in the daily briefing and not released if not. The Code of Practice for Statistics requires that official statistics should be released in an orderly and timely way at intervals that meet the needs of users as far as practicable. Given their public value, we regret that these statistics have not yet been consistently published on a regular basis. The Department for Transport should commit to publication at a specified time – say noon or 2pm – and on specified days, in a similar way to other COVID-related data such as the Public Health England deaths figures.


  • You have published a methodology note to accompany these statistics which clearly explains the data sources used, as well as any limitations or data quality issues and how these impact the trends presented. It is reassuring that where possible, you have used the same methodology for these statistics as is used in the related National Statistics publication and, where necessary, you have adapted the methodology to mitigate data quality issues related to the near-to real-time reporting period. Based on the availability of data, you have taken a practical approach to the choice of baselines to show the change in transport use over time.
  • You have implemented a thorough and robust quality assurance process to ensure that these statistics are high quality and mitigate the risk of error in the production process. This involves several levels of checks throughout the process and a range of quality assurance methods including comparisons to alternative data sources, use of industry intelligence and sense checks of changes in figures over time.
  • We welcome your commitment to continually improve your published methodology and quality information, for example by including more detailed information about Transport for London data and an explanation of the reason for different baselines used for different modes of transport.

We look forward to seeing these statistics develop as circumstances change. As set out in our guidance on changes to statistical outputs you can include a statement in your methodology note such as “These statistics have been produced quickly in response to developing world events. The Office for Statistics Regulation, on behalf of the UK Statistics Authority, has reviewed them against several key aspects of the Code of Practice for Statistics and regards them as consistent with the Code’s pillars of Trustworthiness, Quality and Value.”

I am copying this letter to Julie Stanborough, Deputy Director of the COVID-19 Press Data Team at the Cabinet Office.

Yours sincerely


Ed Humpherson

Director General for Regulation