Institute of Epidemiology & Health Care


Applying to use the ONS LS

ONS SRS and CeLSIUS response to COVID-19

The ONS SRS Safe Settings and UCL offices were closed in March 2020, 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 at least four months to be approved. 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.


Applying to use the ONS LS

ONS accommodates and promotes use of the LS yet must ensure the confidentiality of the individuals in the sample. Researchers therefore need to make an application and undergo secure data training in order to access the LS. 

The application procedures are outlined below, but before applying:

Apply to use LS data

To use LS data, researchers must complete an ONS Longitudinal Study Supplementary form (Word) and a Research Project Accreditation Application (Word) form. This last form asks for evidence of an ethics consideration for your research project:

  • ONS ethics self-assessment information with links to self-assessment guidance and self-assessment form

All of the project's researchers are named on the Research Project Accreditation Application form and each researcher is asked to say whether they will be:

An 'Accredited Researcher'

ONS refers to initial research outputs as 'pre-publication outputs'. Any LS researcher wishing to see and/or use these outputs, whether in an ONS secure setting or on their own computer, must hold ONS Researcher Accreditation. This involves:

Or a 'Peer Reviewer with access to data'

i.e. a researcher who accesses the data in a secure setting (e.g. one of the ONS secure research rooms) to validate previous analysis and who has access to cleared outputs from the research (i.e. pre-publication clearances). In this case, the researcher must also:

Or a 'Peer Reviewer with access to cleared outputs only'

i.e. a researcher who does not access the data, but does have access to cleared, non-disclosive outputs (i.e. pre-publication clearances). They do not need to be a full Accredited Researcher but they will need to sign a confidentiality agreement which ONS will send to the project's lead researcher.

Send your completed forms to celsius@ucl.ac.uk so that we may help you to finalise them to the standards required by ONS - but feel free to contact us at any point for assistance with your application.

We currently estimate that from submission of your application to CeLSIUS to full and final approval you should allow at least four months to be approved. ONS will contact you to inform you of your project's approval and will ask you to complete Controlled Access Security Operating Procedures (SyOPs) and Researcher Data Access Agreement (DAA) forms, which they will forward to you by email.

Undergo LS secure data training

Approved Accredited Researchers will be invited by ONS to attend a day of secure data training either online or at one of the ONS office locations. Please note:

  • CeLSIUS LS user support staff will not be allowed to release any outputs for a project until Accredited Researchers have been trained

See doing your LS research for information on what happens once your project has been approved.