The Absolute Risk Reduction (ARR) Calculator helps you understand the direct benefit of an intervention. By comparing event rates in control and experimental groups, it quantifies how much a treatment reduces the risk of an adverse outcome. Essential for evidence-based medicine and clinical trial analysis.
Formula:
The Absolute Risk Reduction (ARR) is calculated as the difference between the Control Event Rate (CER) and the Experimental Event Rate (EER).
Formula:
ARR = CER - EER
Where:
CER = (Events in Control Group / Total in Control Group)EER = (Events in Experimental Group / Total in Experimental Group)
The result is often expressed as a percentage by multiplying by 100%.