Estimating average regression effect under non-proportional hazards [PDF]
Biostatistics, 2000 We present an estimator of average regression effect under a non-proportional hazards model, where the regression effect of the covariates on the log hazard ratio changes with time. In the absence of censoring, the new estimate coincides with the usual partial likelihood estimate, both estimates being consistent for a parameter having an interpretation
Ronghui Xu
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A Federated Cox Model with Non-Proportional Hazards
, 2022 Recent research has shown the potential for neural networks to improve upon classical survival models such as the Cox model, which is widely used in clinical practice. Neural networks, however, typically rely on data that are centrally available, whereas healthcare data are frequently held in secure silos.
Dekai Zhang +2 more
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On penalized likelihood estimation for a non-proportional hazards regression model. [PDF]
Stat Probab Lett, 2013 In this paper, a semi-parametric generalization of the Cox model that permits crossing hazard curves is described. A theoretical framework for estimation in this model is developed based on penalized likelihood methods. It is shown that the optimal solution to the baseline hazard, baseline cumulative hazard and their ratio are hyperbolic splines with ...
Devarajan K, Ebrahimi N.
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A Multiple kernel testing procedure for non-proportional hazards in factorial designs
, 2022 In this paper we propose a Multiple kernel testing procedure to infer survival data when several factors (e.g. different treatment groups, gender, medical history) and their interaction are of interest simultaneously. Our method is able to deal with complex data and can be seen as an alternative to the omnipresent Cox model when assumptions such as ...
Marc Ditzhaus +2 more
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Methods for non-proportional hazards in clinical trials: A systematic review [PDF]
Statistical Methods in Medical ResearchFor the analysis of time-to-event data, frequently used methods such as the log-rank test or the Cox proportional hazards model are based on the proportional hazards assumption, which is often debatable. Although a wide range of parametric and non-parametric methods for non-proportional hazards has been proposed, there is no consensus on the best ...
Maximilian Bardo +15 more
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Restricted mean survival time approach versus time-varying coefficient Cox model for quantifying treatment effect when hazards are non-proportional [PDF]
BMC Medical Research MethodologyBackground Although the Cox time-varying coefficient (TVC) model has been developed to address non-proportional hazard (PH), its use remains underexplored.
Tianyuan Gu +4 more
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Group Sequential Design Under Non-proportional Hazards
, 2023 Non-proportional hazards (NPH) are often observed in clinical trials with time-to-event endpoints. A common example is a long-term clinical trial with a delayed treatment effect in immunotherapy for cancer. When designing clinical trials with time-to-event endpoints, it is crucial to consider NPH scenarios to gain a complete understanding of design ...
Yujie Zhao +3 more
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Comparison between asymptotic and re-randomisation tests under non-proportional hazards in a randomised controlled trial using the minimisation method [PDF]
BMC Medical Research MethodologyBackground Pocock-Simon’s minimisation method has been widely used to balance treatment assignments across prognostic factors in randomised controlled trials (RCTs).
Ryusei Kimura +3 more
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Converging or Crossing Curves: Untie the Gordian Knot or Cut it? Appropriate Statistics for Non-Proportional Hazards in Decitabine DACO-016 Study (AML). [PDF]
Adv Ther, 2015 Tomeczkowski J +7 more
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Summary measures in non-inferiority clinical trials with a time-to-event outcome: an empirical comparison of power [PDF]
BMC Medical Research MethodologyBackground Time-to-event data is commonly used in non-inferiority clinical trials. While the hazard ratio is a popular summary measure in this context, the difference in restricted mean survival time has been theoretically shown to increase power and ...
S. D. Lana Broer +5 more
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