Development of a new adapted Quintet Recruitment Intervention (QRI-Two) for rapid application to RCTs underway with enrolment shortfalls - to identify previously hidden barriers and improve recruitment

Background
Many randomised controlled trials (RCTs) struggle to recruit, despite valiant efforts. The QRI (QuinteT Recruitment Intervention) uses innovative research methods to optimise recruitment by revealing previously hidden barriers related to the perceptions and experiences of recruiters and patients, and targeting remedial actions. It was designed to be integrated with RCTs anticipating difficulties at the outset. A new version of the intervention (QRI-Two) was developed for RCTs already underway with enrolment shortfalls.

Methods
QRIs in 12 RCTs with enrolment shortfalls during 2007–2017 were reviewed to document which of the research methods used could be rapidly applied to successfully identify recruitment barriers. These methods were then included in the new streamlined QRI-Two intervention which was applied in 20 RCTs in the USA and Europe during 2018–2019. The feasibility of the QRI-Two was investigated, recruitment barriers and proposed remedial actions were documented, and the QRI-Two protocol was finalised.

Results
The review of QRIs from 2007 to 2017 showed that previously unrecognised recruitment barriers could be identified but data collection for the full QRI required time and resources usually unavailable to ongoing RCTs. The streamlined QRI-Two focussed on analysis of screening/accrual data and RCT documents (protocol, patient-information), with discussion of newly diagnosed barriers and potential remedial actions in a workshop with the RCT team. Four RCTs confirmed the feasibility of the rapid application of the QRI-Two. When the QRI-Two was applied to 14 RCTs underway with enrolment shortfalls, an array of previously unknown/underestimated recruitment barriers related to issues such as equipoise, intervention preferences, or study presentation was identified, with new insights into losses of eligible patients along the recruitment pathway. The QRI-Two workshop enabled discussion of the newly diagnosed barriers and potential remedial actions to improve recruitment in collaboration with the RCT team. As expected, the QRI-Two performed less well in six RCTs at the start-up stage before commencing enrolment.

Conclusions
The QRI-Two can be applied rapidly, diagnose previously unrecognised recruitment barriers, and suggest remedial actions in RCTs underway with enrolment shortfalls, providing opportunities for RCT teams to develop targeted actions to improve recruitment. The effectiveness of the QRI-Two in improving recruitment requires further evaluation.