Journal Article

DKFZ-2025-02651

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png Revisiting Hazard Ratios: Can We Define Causal Estimands for Time-Dependent Treatment Effects?

Edelmann, D. (Last author)DKFZ*

2025
Wiley-VCH Berlin

Abstract: In this paper, some aspects concerning the causal interpretation of hazard contrasts are revisited. It is first investigated, in which sense the hazard ratio constitutes a causal effect. It is demonstrated that the hazard ratio at a timepoint t $t$ represents a causal effect for the population at baseline, but in general not for any population at risk at time t $t$ . Moreover, the scenario is studied, in which the survival curves coincide up to some timepoint t $t$ and then separate. This investigation provides valuable insight both on the causal interpretation of the conventional hazard ratio and on properties of the recently proposed causal hazard ratio. The findings suggest that, without making further assumptions, there is in general no meaningful estimand for a treatment effect at time t > 0 $t > 0$ . It is therefore advocated to develop alternative estimands grounded in medically plausible assumptions about the joint distribution of counterfactual survival times.

Keyword(s): Proportional Hazards Models (MeSH) ; Humans (MeSH) ; Causality (MeSH) ; Survival Analysis (MeSH) ; Time Factors (MeSH) ; Treatment Outcome (MeSH) ; Data Interpretation, Statistical (MeSH) ; Biometry: methods (MeSH)

Note: #LA:C060#

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Contributing Institute(s):

1. C060 Biostatistik (C060)

Research Program(s):

1. 313 - Krebsrisikofaktoren und Prävention (POF4-313) (POF4-313)

Appears in the scientific report 2025

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Database coverage:
; ; BIOSIS Previews ; Biological Abstracts ; Clarivate Analytics Master Journal List ; DEAL Wiley ; Essential Science Indicators ; IF < 5 ; JCR ; Nationallizenz ; SCOPUS ; Science Citation Index Expanded ; Web of Science Core Collection

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