Institute of Epidemiology & Health Care


Using the ONS Longitudinal Study

ONS SRS and CeLSIUS response to COVID-19

The ONS SRS Safe Settings and UCL offices were closed in March, in accordance with government guidelines, and will remain closed until further notice. CeLSIUS is able to offer remote user support for ONS LS projects - please contact us via celsius@ucl.ac.uk.

LS project support will be prioritised in the following order:

1) of immediate government interest – e.g. covid-19
2) examined work nearing deadline (before July 31st 2020)
3) work only using the LS nearing study period end (before July 31st 2020)
4) work using the LS nearing study period end (before July 31st 2020)
5) ongoing work only using the LS
6) new work only using the LS 
7) other work
Please note:
  • We will still accept and process new applications to use the LS but we estimate that, from application submission to final approval, you should allow a minimum of ten weeks. Also, support for these once they are approved will be limited for the time being.
  • Large scale cross tabs and other work involving extensive manipulation to prevent disclosure will not be cleared.
  • New x-file (restricted variables) requests may be submitted, but ONS can only review them and cannot prepare/provide access to them. If you have already been given access to an x-file dataset, however, you will still be able to access it.
  • Additionally, approved researchers can apply to access their existing projects from home subject to guidelines set out by ONS on accessing secure research data as an accredited researcher.

Thank you for your patience while this remote service is in place.


ONS Longitudinal Study data is available for free to researchers who can show that their work is in the public interest. In order to maintain the confidentiality of the individuals in the LS data sample, the data can only be accessed in secure settings at ONS offices in London, Newport (South Wales) and Titchfield (Hampshire), and researchers need to apply to use it.

CeLSIUS will guide and support you throughout the application process and whilst you conduct your research. Furthermore, you may send code (e.g. in STATA, SPSS or SAS) to be run in your absence, or discuss with CeLSIUS the outputs that you require (perhaps constructing specimen tables or models) and we will write and run code for you. Also, you may specify an aggregated dataset (which will have a limited number of values) for you to analyse at your place of study/work.

See below for full explanations of how to access and use the ONS Longitudinal Study.


Thinking of using the ONS LS?

All you need to know to get started


Applying to use the ONS LS

How to access the data


Doing your LS research

Find out what happens once your LS project has been approved


Disseminating your results

What to do when you wish to present or publish the results of your research

Celsius Resources


Sources of information and guidance