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Top 5 Retention Tips


Offering monetary incentives may increase retention: see Cochrane review.


Newsletters are widely used as a retention intervention but the evidence to support their use is of very low certainty.  Evaluations of newsletter compared to no newsletter would be welcome.


The Trial Forge SWAT Network intends to publish a priority list of retention intervention in need of evaluation in Studies Within A Trial (SWATs) soon.  Watch this space..


More to come: keep checking the site…


More to come: keep checking the site…

More About Retention

Most trials involve more than one contact with a participant after they have been recruited, allowing for data collection over a pre-defined period of time. This contact comes in many forms; some examples include face-to-face meetings, through letters, the internet, telephone calls, text messaging, email or the return of medical test kits. Missing data can result from any of these data collection methods, sometimes people are too busy to reply, they have changed their mind and no longer want to participate in the study, or they may have experienced unwanted or unexpected side effects as a result of trial participation.

The attrition of trial participants can impact negatively on the trial’s results. Bias can be introduced if participants drop-out as a result of experiencing severe side effects, and the study can be underpowered if attrition rates are substantial.

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