What is it?
Participants receive a self-sampling kit along with a reminder and a leaflet.
Does it work?
Using a self-sampling kit probably increases retention .
How big is the effect?
An increase of 9% (95% confidence interval = 4% to 13%).
How certain are we?
GRADE Moderate certainty.
We recommend that trialists use self-sampling kits to increase retention in trails for which this is possible.
How can I use this straight away?
See Resource bundle below for details on how to use self-sampling kits.
Imagine initial retention is 65% of those approached. You have a trial with 100 participants that needs responses from 80 to meet its statistical power calculations. Retention of 65% means that you will be 15 responses short (see chart below).
Now imagine using self-sampling kits. The chart below shows the impact of an absolute increase of 9% (95% CI = 4% to 13%). Retention is now 78%, which means our best estimate is that you would now be only 2 responses short.
*Random effects model done using Comprehensive Meta-Analysis v4 (www.meta-analysis.com).
Differences >0% favour the intervention. The GRADE assessment is low because of the imprecision of a single study.
How to Cite
Citation: Ostrovska B. Evidence pack– Retention: Self-sampling kits (RET25), 2023, https://www.trialforge.org/retention-sector/self-sampling-kits-id-ret25/.
- This summary is from the Cochrane review of strategies to improve retention in randomised trials (https://www.cochranelibrary.com/cdsr/doi/10.1002/14651858.MR000032.pub3/full).
- The ‘Does it work?’ statement is structured according to effect size and GRADE certainty as per GRADE Guidelines 26 (https://doi.org/10.1016/j.jclinepi.2019.10.014). The statement is for large effect size and Moderate GRADE certainty.
- The recommendation statement is the consensus view of the authors of this summary based on the GRADE certainty and features of the trials contributing to the evidence.
- If you have any questions contact email@example.com.