What influences recruitment to randomised controlled trials? A review of trials funded by two UK funding agencies

2006

Factors Influencing Recruitment to Randomised Controlled Trials

Sample size: 114 publication 10 minutes Evidence: moderate

Author Information

Author(s): Alison M McDonald, Rosemary C Knight, Marion K Campbell, Vikki A Entwistle, Adrian M Grant, Jonathan A Cook, Diana R Elbourne, David Francis, Jo Garcia, Ian Roberts, Claire Snowdon

Primary Institution: Health Services Research Unit, University of Aberdeen

Hypothesis

What factors are associated with good and poor recruitment in multicentre trials funded by UK public bodies?

Conclusion

Many trials experienced recruitment difficulties, and addressing the trial question may be more important than recruitment alone.

Supporting Evidence

Only 31% of trials achieved their original recruitment target.
41% of trials experienced delays in starting recruitment.
63% of trials reported early recruitment problems.
Half of the trials required an extension to their recruitment period.

Takeaway

This study looked at why some medical trials have a hard time getting enough people to join. It found that many trials struggle to meet their goals for how many participants they need.

Methodology

The study reviewed 114 trials funded by the MRC and HTA, analyzing trial characteristics and recruitment success using Chi-squared and Fisher's exact tests.