RRR
Also written as: RRR — Relative Risk Reduction
Relative risk reduction; percentage decrease in event rate comparing intervention to control groups.
Full Definition
Relative risk reduction (RRR) is a statistical measure that expresses the proportional reduction in adverse events achieved by an intervention compared to a control group. RRR is calculated as the absolute difference in event rates divided by the control group event rate, expressed as a percentage. While RRR provides important information about treatment efficacy, it can be misleading without considering baseline risk and absolute risk reduction. In cardiovascular prevention, RRR values are often impressive (e.g., 30-40% reduction in cardiovascular events with statins), but the absolute benefits depend heavily on individual patient risk profiles.
Usage
Usage note: Always present alongside absolute risk reduction and baseline risk information.
In Context
- "The study reported a 35% RRR for cardiovascular events, but the absolute risk reduction was only 2%." — Critical appraisal of clinical evidence
- "RRR data should be presented alongside absolute risk information for proper clinical interpretation." — Evidence-based medicine guideline