How is RRR Different from Absolute Risk Reduction (ARR)?
While Absolute Risk Reduction (ARR) provides the absolute difference in event rates between the control and experimental groups, RRR offers a proportional reduction in risk. For example, if a treatment reduces the risk of an event from 10% in the control group to 5% in the treatment group, the ARR is 5% (10% - 5%), whereas the RRR is 50% [(10% - 5%)/10%].
