Keeping it credible in cohort multiple Randomised Controlled Trials: the Community Ageing Research 75+ (CARE 75+) study model of patient and public involvement and engagement

Plain english summary There are well documented benefits to involving patients and the public in research. However, there is little research published about their involvement in large complex studies such as cohort multiple Randomised Controlled Trials (cmRCTs). The cmRCT method establishes a group of participants, with a common characteristic (e.g. older people) who will be followed over a number of years. Other (sub) studies can also recruit from this pool of people. This method offers researchers many advantages, including being able to recruit from more hard to reach groups. However, cmRCTs also have features which can make it more complicated to involve patients and the public. For example more than one study may take place at the same time; studies may be spread out over a large geographical area and they may include a wide range of topics. In spite of these difficulties we have developed a way of working with patients, the public and researchers that provides stability over time but allows flexibility along the way. Our model of working has saved us time and money; helped us to recruit more widely, and enabled us to focus our research in areas that are important to older people with frailty.Abstract Background There is increasing guidance on how to make the most of the rich seam of data provided by large cohort studies, and growing recognition of the benefits of cohort multiple Randomised Controlled Trials (cmRCT) in health research. In contrast, there is a lack of discussion about patient and public involvement and engagement (PPIE) in these large and complex research infrastructures. Our aim was to create a structure to enable meaningful, sustainable public involvement within the cmRCT framework. We have established a core reference group of four key individuals with extensive links to other relevant local community structures and individuals. Results Using the CARE 75+ model we have engaged with a wide variety of patients and the public in a relatively short space of time. Activities have included scrutiny of protocols and assessment tools, and process evaluations; resulting in system efficiencies, increased recruitment and a more focused research agenda. Conclusions There is a need for strong public oversight and flexible models of PPIE in cmRCTs. The model of PPIE developed in the Community Ageing Research 75+ study presents one potential way to foster expertise and enable diversity.