Background
Recruitment of participants with cancer from clinical settings into studies is commonly reported as slow. The introduction of national support systems and infrastructure in the United Kingdom, such as the National Cancer Research Network (NCRN), aims to increase the number of patients participating in high quality clinical research studies. This includes funding for clinical research nurses to support recruitment into such studies. Since the NCRN was established in 2001 the recruitment rate to high quality clinical research cancer trials on their portfolio has doubled. However, there is limited published data to inform researchers planning new studies as to the actual recruitment that they might expect and what may be done to enhance recruitment.

Methods
We have established a prospective, longitudinal cohort study of 1053 people with colorectal cancer, by recruiting from 30 centres across the United Kingdom.

Aim
This work will report details of how this study was set up and how the large cohort were recruited; including the process of selection of participating sites, time to research governance approvals, time to first recruit, rate of recruitment and time to completion of study. The processes to enhance recruitment will be discussed as well as difficulties encountered and recommendations made for future studies.

Findings
The average time taken for each centre to gain all the necessary approvals and be able to start recruiting was 86 working days (range 38- 207). Centres originally agreed to recruit 2-3 patients per week however in reality the average recruitment rate per site was only 0.67 per week. The recruitment of 1000 participants was completed by 30 recruiting centres in 17 month.

Conclusions
This was highly successful recruitment strategy but with a number of challenges that had to be overcome by working in collaboration with the NCRN, research nurses, fund and service users .