Trial Forge Guidance 1: What is a Study Within A Trial (SWAT)

Shaun Treweek* (Corresponding Author), Simon Bevan, Peter Bower, Marion Campbell, Jacquie Christie, Mike Clarke, Clive Collett, Seonaidh Claire Cotton, Declan Devane, Adel El Feky, Ella Flemyng, Sandra Galvin, Heidi Rebecca Gardner, Kate Gillies, Jan Jansen, Roberta Littleford, Adwoa Parker, Craig Ramsay, Lynne Restrup, Frank SullivanDavid Torgerson, Liz Tremain, Matthew Westmore, Paula R. Williamson

*Corresponding author for this work

Research output: Contribution to journalLetterpeer-review

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Randomised trials are a central component of all evidence-informed health care systems and the evidence coming from them helps to support health care users, health professionals and others to make more informed decisions about treatment. The evidence available to trialists to support decisions on design, conduct and reporting of randomised trials is, however, sparse. Trial Forge is an initiative that aims to increase the evidence base for trial decision-making and in doing so, to improve trial efficiency.

One way to fill gaps in evidence is to run Studies Within A Trial, or SWATs. This guidance document provides a brief definition of SWATs, an explanation of why they are important and some practical ‘top tips’ that come from existing experience of doing SWATs. We hope the guidance will be useful to trialists, methodologists, funders, approvals agencies and others in making clear what a SWAT is, as well as what is involved in doing one.
Original languageEnglish
Article number139
Publication statusPublished - 23 Feb 2018


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