Clinical Endpoints
Hazard Ratio
Also known as: HR, Risk ratio
Definition
Statistical measure comparing risk of events (progression or death) between treatment groups in clinical trials.
Detailed Explanation
HR < 1 favors experimental treatment; HR = 0.5 means 50% risk reduction. HR of 0.70 (30% risk reduction) is often clinically meaningful. Used for time-to-event endpoints (PFS, OS). Accompanied by confidence intervals and p-values. Assumes proportional hazards over time.