Abstract
Hazard ratios (HR) associated with the well-known proportional hazard Cox regression models are routinely used for measuring the impact of one factor of interest on a time-to-event outcome. However, if the underlying real model does not fit with the theoretical requirements, the interpretation of those HRs is not clear. We propose a new index, gHR, which generalizes the HR beyond the underlying survival model. We consider the case in which the study factor is a binary variable and we are interested in both the unadjusted and adjusted effect of this factor on a time-to-event variable, potentially, observed in a right-censored scenario. We propose non-parametric estimations for unadjusted gHR and semi-parametric regression-induced techniques for the adjusted case. The behavior of those estimators is studied in both large and finite sample situations. Monte Carlo simulations reveal that both estimators provide good approximations of their respective inferential targets. Data from the Health and Lifestyle Study are used for studying the relationship of the tobacco use and the age of death and illustrate the practical application of the proposed technique. gHR is a promising index which can help facilitate better understanding of the association of one study factor on a time-dependent outcome.
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Author contribution: All the authors have accepted responsibility for the entire content of this submitted manuscript and approved submission.
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Research funding: None declared.
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Conflict of interest statement: The authors declare no conflicts of interest regarding this article.
Appendix: A Technical issues
A.1 Theorem’s proof
Since S
x
(τ
N
) →
N
0 (x = 0, 1) and
Stute [43] proved that, for any continuous function ψ(⋅), in the right-censored context,
where
A.2 Corollary’s proof
We have that
where ς (u) = log(1 − u) − log(u). The result is directly derived from the Delta-method and the previous Theorem. □
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Supplementary Material
As supplementary material we provide the R package generalizedHR which contains the functions used in the Monte Carlo simulation study and in the real-world data example. This package also provides functions for emulating the considered simulation models. Original data can be obtained, under request, at https://beta.ukdataservice.ac.uk/datacatalogue/studies/study?id=2218.
The online version of this article offers supplementary material (https://doi.org/10.1515/ijb-2021-0003).
© 2021 Walter de Gruyter GmbH, Berlin/Boston
Artikel in diesem Heft
- Frontmatter
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- Doubly robust adaptive LASSO for effect modifier discovery
- Increasing the efficiency of randomized trial estimates via linear adjustment for a prognostic score
- Review
- Review and comparison of treatment effect estimators using propensity and prognostic scores
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- Error rate control for classification rules in multiclass mixture models
- Regression trees and ensembles for cumulative incidence functions
- Causal inference under over-simplified longitudinal causal models
- Causal inference under interference with prognostic scores for dynamic group therapy studies
- Bayesian multi-response nonlinear mixed-effect model: application of two recent HIV infection biomarkers
- A Bayesian semiparametric accelerate failure time mixture cure model
- Quantifying the extent of visit irregularity in longitudinal data
- An improved method for analysis of interrupted time series (ITS) data: accounting for patient heterogeneity using weighted analysis
- A robust hazard ratio for general modeling of survival-times
- Penalized likelihood estimation of the proportional hazards model for survival data with interval censoring
- A parametric approach to relaxing the independence assumption in relative survival analysis
- The number of response categories in ordered response models
- A comparison of joint dichotomization and single dichotomization of interacting variables to discriminate a disease outcome
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Artikel in diesem Heft
- Frontmatter
- Research Articles
- Doubly robust adaptive LASSO for effect modifier discovery
- Increasing the efficiency of randomized trial estimates via linear adjustment for a prognostic score
- Review
- Review and comparison of treatment effect estimators using propensity and prognostic scores
- Research Articles
- Error rate control for classification rules in multiclass mixture models
- Regression trees and ensembles for cumulative incidence functions
- Causal inference under over-simplified longitudinal causal models
- Causal inference under interference with prognostic scores for dynamic group therapy studies
- Bayesian multi-response nonlinear mixed-effect model: application of two recent HIV infection biomarkers
- A Bayesian semiparametric accelerate failure time mixture cure model
- Quantifying the extent of visit irregularity in longitudinal data
- An improved method for analysis of interrupted time series (ITS) data: accounting for patient heterogeneity using weighted analysis
- A robust hazard ratio for general modeling of survival-times
- Penalized likelihood estimation of the proportional hazards model for survival data with interval censoring
- A parametric approach to relaxing the independence assumption in relative survival analysis
- The number of response categories in ordered response models
- A comparison of joint dichotomization and single dichotomization of interacting variables to discriminate a disease outcome
- Spike detection for calcium activity