Strategies to address recruitment to a randomised trial of surgical and non-surgical treatment for cancer – results from a complex recruitment intervention within the Mesothelioma and Radical Surgery 2 (MARS 2) study

Objectives: Recruiting to randomised trials is often challenging particularly when the intervention arms are markedly different. The MARS 2 randomised controlled trial compared standard chemotherapy with or without (extended) pleurectomy decortication surgery for malignant pleural mesothelioma. Anticipating recruitment difficulties, a QuinteT Recruitment Intervention (QRI) was embedded in the main trial phase to unearth and address barriers. The trial achieved recruitment to target with a 4-month COVID-19 pandemic related extension. This paper presents the key recruitment challenges, and the strategies delivered to optimise recruitment and informed consent.

Design: A multi-faceted, flexible, mixed method approach to investigate recruitment obstacles drawing on data from staff/patient interviews, audio-recorded study recruitment consultations and screening logs. Key findings were translated into strategies targeting identified issues. Data collection, analysis, feedback, and strategy implementation continued cyclically throughout the recruitment period.

Setting: Secondary thoracic cancer care

Results: Respiratory physicians, oncologists, surgeons, and nursing specialists supported the trial, but recruitment challenges were evident. The study had to fit within a framework of a thoracic cancer service considered overstretched where patients encountered multiple healthcare professionals and treatment views, all of which challenged recruitment. Clinician treatment biases, shaped in part by the wider clinical and research context alongside experience, adversely impacted several aspects of the recruitment process by restricting referrals for study consideration, impacting eligibility decisions, affecting the neutrality in which the study and treatment was presented and shaping patient treatment expectations and preferences. Individual and group recruiter feedback and training raised awareness of key equipoise issues, offered support, and shared good practice to safeguard informed consent and optimise recruitment.

Conclusions: With bespoke support to overcome identified issues, recruitment to a challenging RCT of surgery versus no surgery in a thoracic cancer setting with a complex recruitment pathway and multiple health professional involvement is possible.