Reflecting on the methodological challenges of recruiting to a United Kingdom-wide, multi-centre, randomised controlled trial in gynaecology outpatient settings

Successful recruitment of participants to any trial is central to its success. Trial results are routinely published, and recruitment is often cited to be slower and more difficult than anticipated. This article reflects on the methodological challenges of recruiting women with prolapse attending United Kingdom (UK) gynaecology outpatient clinics to a multi-centre randomised controlled trial (RCT) of physiotherapy, and the systems put in place in an attempt to address them. Gynaecology outpatients with symptomatic prolapse were to be recruited over a 16-month period from 14 UK hospitals and one New Zealand hospital. Eligible women were informed about the trial by their gynaecologist and informed consent was obtained by the central trial office. Recruitment difficulties were encountered early on, and a number of strategies were employed to try to improve recruitment. Some strategies were more successful than others and they differed in the resources required. Actions that facilitated recruitment included increasing recruiting centres to 23 UK and two international hospitals, good centre support, using processes embedded in clinical practice, and good communication between the trial office, collaborators and participants. Collaborator incentives, whereby staff involved received the benefit immediately, were more successful than a nominal monetary payment per woman randomised. Barriers to recruitment included fewer eligible women than anticipated, patient's preference to receive active treatment rather than allocation to the control group, lack of support staff and high staff turnover. Geographical variations in Primary Care Trust Research Management and Governance approval systems and general practitioner (GP) referral procedures also impacted negatively on recruitment. Our article reflects on the methodological challenges of recruiting to a multi-centre RCT in a UK gynaecology setting. Effective interventions included increasing the number of recruiting centres and providing collaborator incentives. Barriers to recruitment included fewer eligible women than anticipated, patient's preference to be allocated to the treatment group, lack of support staff, and variations in approval systems and GP referral procedures. To improve the evidence base on clinical trial recruitment, trialists need to publish their experiences and lessons learned. Future RCTs should evaluate, where possible, the effect of strategies designed to improve recruitment and retention. Curre