Welcome to ORRCA

The ORRCA project (Online Resource for Research in Clinical triAls) aims to bring together published and ongoing work in the field of recruitment and retention research into a searchable database. 

ORRCA covers literature published upto the end of 2017. We are currently working on updates for 2018 and 2019 publications which will be added as they become available. Authors are welcome to submit papers as soon as they are published. Last update: 08/03/2021

If you use the ORRCA database, please reference it in any reports or publications citing:

Kearney, A., Harman, N. L., Rosala-Hallas, A., Beecher, C., Blazeby, J. M., Bower, P., … Gamble, C. (2018). Development of an online resource for recruitment research in clinical trials to organise and map current literature. Clinical Trials, 15(6), 533–542. https://doi.org/10.1177/1740774518796156

Retention strategies: Updated systematic review of nested randomised studies of retention interventions in clinical trials Read more

NEW SWAT: Assessment of an optimised patient brochure and cover letter developed by MRC START for use in a lung cancer screening trial. Read more

The PRioRiTy study in partnership with the James Lind Alliance consensus exercise to decide the top 10 recruitment research questions. Read more

Treweek and colleagues have updated their systematic review of 'Strategies to improve recruitment to randomised trials'.  Read more

To suggest an alternative classification for an article please email us using our contact page