Findings

What do systematic reviews say?

1 questions · 1 findings · 1 reviews

No studies found 0 · 0%GRADE not reported 0 · 0%Very low 1 · 100%Low 0 · 0%Moderate 0 · 0%High 0 · 0%

Retention [ · trial participants being followed up for data collection

It is very uncertain whether maintaining participant engagement: newsletter changes retention [ compared with usual follow‐up (very low certainty).

1 finding from 1 review

Strategies to improve retention in randomised trials 2021 · Cochrane Headline outcomes only
RR 0.99 [0.95, 1.04]
4 studies · 5622 participants
Very low