Institute of Epidemiology & Health Care


Want to use the ONS LS for your research?

First of all, tell us your research idea!

Email us at celsius@ucl.ac.uk outlining your research idea, and why you want to use the LS.

We'll check the LS is suitable

We will discuss with you the suitability of the LS for your research.

Apply for researcher accreditation

You'll need to hold ONS Researcher Accreditation before using the LS. But if you haven't got this, we'll guide you on applying for it via the Research Accreditation Service.

Draft your application

We'll work with you to develop your application. This will involve completing a Research Project Accreditation Application form (Word) (with this guidance), an ONS Longitudinal Study Supplementary form (Word) and an Ethics Self-Assessment sheet (Excel) - please note that this sheet is partially completed and applicants must not change the completed cells. Drafting your application may take a few weeks. 

Information to include: your research abstract, purpose and methodology; details of the datasets required; evidence of ethics consideration (contact celsius@ucl.ac.uk for further guidance); and a detailed list of the LS variables required (which can be viewed in the CeLSIUS data dictionary).*

We'll submit your application on your behalf Once you are happy with your application, and we're confident that your project stands a good chance of approval, we'll transfer it to ONS' online Research Accreditation Service (RAS) on your behalf.

*For guidance on completing the above forms, see our webinar: Applying to use the ONS Longitudinal Study: A guide to completing the forms.

Answer queries

The application is subject to initial feasibility and public good checks by the ONS SRS Customer Support team, and Data Owner approval is sought. Both of these bodies may request further information on the project (e.g. on the methodology), so researchers are sometimes asked for more details or clarification. Again, CeLSIUS will work with you to answer any queries and submit more information if necessary.

Wait for your project to be approved

The final decison on whether to approve a project is made by the UKSA using a framework agreed and overseen by the Research Accreditation Panel (RAP). It usually takes three months after the application is submitted to reach the RAP for a final decision.

Access your LS data!

Once your project has been approved, ONS checks that all your research team members are appropriately accredited for their roles in the project. CeLSIUS  will then extract the data you require from the LS database and place it in your designated project folder for you to access within a secure research setting. It is usually takes a month between having your project approved and being able to access your data.

Doing your ONS LS research explains what happens once your LS research has begun.