Study within a trial (SWAT) protocol. Investigating the effect of personalised versus non - personalised study invitations on recruitment: An embedded randomised controlled recruitment trial

Joanne Woodford, Kajsa Norback, Josefin Hagstrom, Helena Gronqvist, Adwoa Parker, Catherine Ellen Arundel, Louise von Essen

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Introduction : Recruitment into clinical trials is a common challenge experienced by health care re searchers. Currently, there is little evidence regarding strategies to improve recruitment into clinical trials. However, preliminary research suggests the personalisation of study invitation letters may increase recruitment rates. As such, there is a need to investigate the effectiveness of personalisation strategies on trial recruitment rates. This study within a trial (SWAT) will investigate the effect of personalised versus non-personalised study invitation letters on recruitment rates into the host trial ENGAGE, a feasibility study of an internet - administered, guided, Cognitive-Behavioural Therapy (CBT) based self-help intervention for parents of children previously
treated for cancer.
Methods : An embedded randomised controlled trial (RCT) will investigate the effectiveness of a personalised study invitation letter including the potential participant’s name and address compared with a standard, non-personalised letter without name or address, on participant recruitment rates into the ENGAGE study. The primary out come is differences in the proportion of participants recruited, examined using logistic regression. Results will be reported as adjusted odds ratios with 95% confidence intervals.
Discussion : Even moderate effects of the personalisation of study invitation letters on recruitment rates could be of significant value by shortening study length, saving resources, and providing a faster answer to the clinical question posed by the study. This protocol can be used as a template for other researchers who wish to contribute to the evidence base for trial decision-making, by embedding a similar SWAT into their trial.
Trial registration : IS RCTN 57233429; IS RCTN 18404129; SWAT 112, Northern Ire land Hub for Trials Methodology Re search SWAT repository (2018 OCT 1 1231).
Original languageEnglish
Article number100572
Number of pages6
JournalContemporary Clinical Trials Communications
Early online date24 Apr 2020
Publication statusPublished - 1 Jun 2020

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© 2020, The Authors. Published by Elsevier Inc.

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