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. 2017 Apr;22(4):484-486.
doi: 10.1634/theoncologist.2016-0198. Epub 2017 Mar 17.

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

Andreas Sashegyi  1 , David Ferry  2
Affiliations

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

Andreas Sashegyi et al. Oncologist. 2017 Apr.

Abstract

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. The Oncologist 2017;22:484-486.

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Conflict of interest statement

Disclosures of potential conflicts of interest may be found at the end of this article.

Figures

Figure 1.
Figure 1.
Exponential survival distributions for an experimental arm (a) and a control arm (b). Distributional forms are SE(x)=exp⁡(−rθx) for (a) and SC(x)=exp⁡(−θx) for (b), assuming hazard rate θ= 0.116 for the control arm (yielding median survival of 6 months) and hazard ratio r= 0.60. Absolute survival benefit is maximized at x=(1/θ)(log⁡r/(r−1)).
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