Recruiting general practitioners and patients with dementia into a cluster randomised controlled trial: strategies, barriers and facilitators.

Background: Recruitment of general practitioners (GPs) and their patients is reported as one of the most challenging steps when undertaking primary care research. The present paper describes the recruitment process of a cluster randomised controlled trial (cRCT) aiming to improve dementia care in the primary care setting.
Methods: Recruitment data was analysed descriptively using frequency tables to investigate comparisons of recruitment rates and results of different recruitment strategies as well as reasons for participation and non-participation of GPs, patients with dementia (PwD) and their caregivers.
Results: Over a period of 23 months, N = 28 GPs were successfully included in the cRCT. This represents an overall recruitment rate of 4.6%. The most efficient strategy in terms of high response and low labour-intensity involved the dissemination of calls for participation in a GP research network. Most frequently reported reasons for GP's participation were Improvement of patient's well-being (n = 22, 79%) followed by Interest in dementia research (n = 18, 64%). The most common reasons for non-participation were Lack of time (n = 71, 34%) followed by Not interested in participation (n = 63, 30%). On a patient level, N = 102 PwD were successfully recruited. On average, each GP referred about n = 7 PwD (range: 1-17; mdn = 6; IQR = 3.5) and successfully recruited about n = 4 PwD (range: 1-11; mdn = 3; IQR = 3.5).
Conclusion: First, our findings propose GP research networks as a promising strategy to promote recruitment and participation of GPs and their patients in research. Second, present findings highlight the importance of including GPs and their interests in specific research topics in early stages of research in order to ensure a successful recruitment. Finally, results do not support cold calls as a successful strategy in the recruitment of GPs.
Trial Registration: The trial was prospectively registered with the ISRCTN registry (Trial registration number: ISRCTN15854413 ). Registered 01 April 2019.