Addressing barriers and identifying facilitators to support informed consent and recruitment in the Cavernous malformations A Randomised Effectiveness (CARE) pilot phase trial: insights from the integrated QuinteT recruitment intervention (QRI).

Background: It was anticipated that recruitment to the Cavernous malformations: A Randomised Effectiveness (CARE) pilot randomised trial would be challenging. The trial compared medical management and surgery (neurosurgical resection or stereotactic radiosurgery) with medical management alone, for people with symptomatic cerebral cavernous malformation (ISRCTN41647111). Previous trials comparing surgical and medical management for intracranial vascular malformations failed to recruit to target. A QuinteT Recruitment Intervention was integrated during trial accrual, September 2021-April 2023 inclusive, to improve informed consent and recruitment.

Methods: The QuinteT Recruitment Intervention combined iterative collection and analysis of quantitative data (28 trial site screening logs recording numbers/proportions screened, eligible, approached and randomised) and qualitative data (79 audio-recorded recruitment discussions, 19 interviews with healthcare professionals, 11 interviews with patients, 2 investigator workshops, and observations of study meetings, all subject to thematic, content or conversation analysis). We triangulated quantitative and qualitative data to identify barriers and facilitators to recruitment and how and why these arose. Working with the chief investigators and trial management group, we addressed barriers and facilitators with corresponding actions to improve informed consent and recruitment.

Findings: Barriers identified included how usual care practices made equipoise challenging, multi-disciplinary teams sometimes overrode recruiter equipoise and logistical issues rendered symptomatic cavernoma diagnosis and assessment for stereotactic radiosurgery challenging. Facilitators identified included the preparedness of some neurosurgeons' to offer surgery to people otherwise offered medical management alone, multi-disciplinary team equipoise, and effective information provision presenting participation as a solution to equipoise regarding management. Actions, before and during recruitment, to improve inclusivity of site screening, approach and effectiveness of information provision resulted in 72 participants recruited following a 5-month extension, exceeding the target of 60 participants.

Interpretation: QuinteT Recruitment Intervention insights revealed barriers and facilitators, enabling identification of remedial actions. Recruitment to a definitive trial would benefit from further training/support to encourage clinicians to be comfortable approaching patients to whom medical management is usually offered, and broadening the pool of neurosurgeons and multi-disciplinary team members prepared to offer surgery, particularly stereotactic radiosurgery.

Funding: National Institute for Health and Care Research.