Which equation represents the absolute risk reduction (ARR)?

The equation for absolute risk reduction (ARR) is correctly represented by the formula where the control event rate is subtracted from the experimental event rate. ARR quantifies the difference in event rates between the control group and the experimental group, providing important information about the effectiveness of an intervention.

In the context of clinical trials, the control group represents individuals who do not receive the treatment, while the experimental group includes individuals who do. By calculating ARR, you can assess how much the risk of a particular outcome is reduced in the experimental group compared to the control group. A higher ARR indicates a more effective intervention, suggesting that more lives or outcomes are positively impacted as a result of the treatment.

The other options don’t accurately reflect this definition: one combines rates rather than showing the difference, while others utilize division or multiplication, which do not pertain to the calculation of risk reduction. Understanding ARR is crucial in evaluating the clinical significance of treatment outcomes.