Table 1.

Components of the QuinteT recruitment intervention as applied within the CARE pilot trial.

Data collectiona	Issues identified
Pre accrual
1. Health care professional workshops 2. Site initiation visits	Small patient pool highlighted importance of including all people with symptomatic brain cavernoma in screening. Usual care practice (monitor until intervention required) rendered equipoise challenging. Shifting usual care practice towards earlier neurosurgical intervention for those presenting with seizures. Variations in application of eligibility criteria and recruiter perception of equipoise via case discussion. Concerns about offering SRS.
During accrual
3. Screening log data	Cross site variation (see Table 2) indicated that at some sites there was: -Exclusion of some people with symptomatic brain cavernoma from entry on screening logs; -Exclusion of some people with symptomatic brain cavernoma from approach; -Variation in proportion of those approached accepting participation.
4. Recruitment discussions (audio recorded)	Recruiter difficulties with: -Conveying equipoise, in particular to those for whom medical management has previously been recommended, those presenting with seizures, those referred for stereotactic radiosurgery (SRS) prior to trial start. -Addressing patient preferences; -Establishing patient equipoise prior to randomisation; -Conveying reason for randomisation. Some patients reluctant for intervention if no longer experiencing symptoms and generally patient preferences favoured less invasive intervention (SRS over neurosurgery, medical management over surgical intervention); Some patients found randomisation within CARE acceptable >12 months post initial presentation of symptoms (note this was counter to recruiter expectations) with some perceiving CARE trial to be offering surgical intervention not otherwise offered outside the trial; Parental equipoise for randomisation between neurosurgery and medical management for small number (N = 3 audio recordings) of paediatric patients.
5. Interviews 1) Healthcare professionals 2) Patients declining or withdrawing from participation	Recruiter controversy: regarding SRS for paediatric participants; regarding SRS for people presenting with symptomatic cavernoma generally and for people presenting with seizures in particular; regarding comparison of surgical interventions vs medical management over the limited timespan of a clinical trial. Some recruiters prepared to offer randomisation to people to whom medical management offered outside the trial. Patient misunderstanding of information provision: monitoring followed by intervention. Patient preferences generally mirrored what they understood to have been recommended by clinicians and generally favoured non-invasive intervention (medical management or SRS) but small number saw trial as means to access surgical intervention not perceived as offered outside of the trial.
6. Observation of trial management group, CARE club discussions, Investigator and research practitioner/coordinator/nurse meetings, trial emails.	Recruiter concerns at approaching prevalent patients, previously recommended medical management. Controversy regarding SRS for paediatric participants, for symptomatic cavernoma generally, for symptomatic cavernoma presenting with seizures specifically. Uncertainty regarding process of referral for SRS within trial. Withdrawal of participants immediately following randomisation, indicating lack of participant equipoise at point of randomisation.
Actions, training, feedbackb	Issues addressed
Pre accrual
7. Co-design of participant facing information	Presentation of equipoise using table comparing processes, benefits and risks of each intervention. Terminology used: ‘treatment including surgery’ vs ‘treatment without surgery’, ‘study’ in place of ‘trial’.
8. QRI site initiation training in information provision	Framing study (UK wide, government funded, in response to uncertainty in evidence base), terminology (as above), presentation of equipoise – 339 views.
9. Co-delivery of site initiation visits	Discussion of site multi disciplinary team and screening processes to maximise N of patients screened for trial. Discussion of case studies to optimise screening for eligibility and encourage equipoise.
During accrual
10. Tips and guidance documents v1 (October 2021) v2 (March 2022) v3 (December 2022)	Framing study (as above), terminology (as above), equipoise (as above) As above, plus addressing patient preferences, explaining reason for randomisation, presenting the surgical intervention arm first (most commonly the non-preferred arm), presenting benefits prior to risks, optimising site screening processes, use of terminology.
11. CARE CI chats: Pre-recorded online discussions involving chief investigators, trial management groups, QRI team exploring relevant issues via 5–10 min conversation (January–May 2022)	Do I really have to do these audio recordings and will they help?—47 views. How to complete screening logs—59 views Screen-as-you-go—27 views Logistics of recruitment—33 views When to randomise?—55 views Approaching patients diagnosed long ago & treated without surgery – 15 views Tips for conversations about the CARE study—26 views Latest top tips for recruitment conversations—6 views Audio Recordings—20 views How to describe randomisation—15 views SRS process for referral—35 views
12. 3x online Investigator and 1x online research nurse/coordinator meetings May–September 2021	Optimising site screening/approach processes, addressing patient preferences, explaining reason for randomisation, presenting the surgical intervention arm first (commonly non-preferred), presenting benefits prior to risks.
13. CARE clubs December–March 2021–22 Live 30 min online discussion meetings to which all principal investigators invited.	Addressing questions about trial/QRI processes.
14. Individual recruiter feedback (doubling as interviews where possible)	Individual feedback to optimise recruitment discussions, including terminology, order of presentation, dealing with participant preferences, establishing participant equipoise prior to randomisation taking place.

^aSome QRI activity simultaneously combined data collection and training/feedback.

^bWeekly CARE Newsflashes and monthly CARE newsletters (emailed to sites teams) reinforced key QRI messages in addition to all above.