1. What Is Relative Risk Reduction?

Relative Risk Reduction (RRR) is a measure of the proportional reduction in risk between treatment and control groups in clinical trials. When derived from hazard ratios, it provides an approximation of the relative benefit of an intervention.

2. How Does The Calculator Work?

The calculator uses the simplified RRR formula:

Where:

• \( RRR \) — Relative Risk Reduction (expressed as decimal, multiply by 100 for percentage)
• \( HR \) — Hazard Ratio from survival analysis

Explanation: This approximation assumes proportional hazards and provides a quick estimate of relative risk reduction from hazard ratio data.

3. Importance Of RRR Calculation

Details: RRR is crucial for understanding the magnitude of treatment effect in clinical trials, helping clinicians and patients comprehend the relative benefit of interventions compared to control conditions.

4. Using The Calculator

Tips: Enter the hazard ratio (HR) value. The calculator will compute the approximate relative risk reduction as a percentage. HR values should be ≥0.

5. Frequently Asked Questions (FAQ)

Q1: What Is The Difference Between RRR And HR?
A: Hazard Ratio (HR) compares event rates over time in survival analysis, while RRR expresses the proportional reduction in risk between groups.

Q2: When Is This Approximation Valid?
A: This approximation works best under proportional hazards assumption and when event rates are relatively constant over time.

Q3: What Does A Negative RRR Mean?
A: A negative RRR indicates increased risk in the treatment group compared to control (HR > 1).

Q4: Are There Limitations To This Approximation?
A: Yes, this is a simplified approximation. More precise calculations may be needed for complex survival analyses or when hazards are not proportional.

Q5: How Should RRR Be Interpreted Clinically?
A: RRR should be considered alongside absolute risk reduction and number needed to treat for complete clinical interpretation.