On the Interpretation of the Hazard Ratio and Communication of Survival Benefit

This brief communication will clarify the difference between a relative hazard and a relative risk. We highlight the importance of this difference, and demonstrate in practical terms that 1 minus the hazard ratio should not be interpreted as a risk reduction in the commonly understood sense of the term. This article aims to provide a better understanding of the type of risk reduction that a hazard ratio implies, thereby clarifying the intent in the communication among practitioners and researchers and establishing an accurate and realistic foundation for communicating with patients.