How much is the lack of retention evidence costing trial teams in Ireland and the UK?

Acknowledgements The authors would like to acknowledge those who provided information regarding the conduct of trials and retention strategies and the costs involved to make the assumptions regarding the conduct of retention strategies in clinical trials that we based the costing model on. Funding This work was supported by a grant from the Health Research Board, Ireland - HRB TMRN 2017-1.Peer reviewedPublisher PD