Challenges of recruiting elderly patients undergoing cardiac surgery - our experience of recruiting 2500 participants in just 30 months at a single centre

Background Emergency operations, cancellations, changing operating theatre schedules, day of surgery arrivals and an aging population are all challenges facing the recruitment of cardiac surgery patients into studies. The observational Coagulation and Platelet Function Testing in Cardiac Surgery (COPTIC) study, which required patients to consent to give blood samples at the start and end of surgery, is the largest of its kind and the largest single study conducted at our hospital. We describe our experience of recruitment and retention and share our successful strategy.