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Methodological Sub-Studies: Studies within a trial or project (SWAT) and studies within a review (SWAR)


Published: 26 May 2022

Version: 2.1 (v2 update 1 March 2023)

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Research studies play a central role in improving health and care in the UK but such studies can be inefficient. Reasons for study inefficiencies include the complex and unpredictable nature of some studies, but more commonly, the lack of evidence to support processes and decision-making.

After a successful pilot conducted in the Health Technology Assessment (HTA) programme, we are now encouraging applicants to embed methodological sub-studies (up to a maximum funding of £30,000) into applications to the following programmes: 

To increase the evidence base, we encourage researchers to embed a study evaluating alternative ways of undertaking a study (e.g. public partnerships, participant recruitment, retention, data collection, evidence synthesis methodology, and engaging with key stakeholders to promote the uptake and use of research by evidence users) to provide evidence about how we can improve the way we perform that process. We welcome proposals that include embedded studies aimed at improving the successful completion of studies.

The findings of SWATs/SWARs are anticipated to be generalisable to other studies but may also be of specific benefit to the host study itself, by supporting delivery process decision points. Applicants who wish to include a methodological sub study in their application should read the relevant sections of the first stage guidance notes for further details.

Applicants who wish to include a SWAT/SWAR in their study should indicate that they intend to do so in their first stage application (there is no need to provide a detailed description of it at this stage).

Supporting information

If you are considering undertaking a SWAT/SWAR within your study, the PROMETHEUS team would be most happy to provide support with setting up the SWAT/SWAR. If this would be useful, please go to the PROMETHEUS website for further information.

PRioRiTy I and PrioRiTy II used James Lind Alliance methodology to work with patients, carers, health professionals, researchers and methodologists to set research priorities around recruitment and retention to clinical trials.