Results 11 to 20 of about 10,758,008 (293)
Quantifying treatment differences in confirmatory trials under non-proportional hazards. [PDF]
J Appl Stat, 2022 Proportional hazards are a common assumption when designing confirmatory clinical trials in oncology. With the emergence of immunotherapy and novel targeted therapies, departure from the proportional hazard assumption is not rare in nowadays clinical research.
Jiménez JL.
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A double-Cox model for non-proportional hazards survival analysis with frailty. [PDF]
Stat Med, 2023 The Cox regression, a semi‐parametric method of survival analysis, is extremely popular in biomedical applications. The proportional hazards assumption is a key requirement in the Cox model. To accommodate non‐proportional hazards, we propose to parameterize the shape parameter of the baseline hazard function using the additional, separate Cox ...
Begun A, Kulinskaya E, Ncube N.
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A Federated Cox Model with Non-Proportional Hazards
CoRR, 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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Adaptive Weight Selection for Time-To-Event Data Under Non-Proportional Hazards. [PDF]
Stat MedABSTRACTWhen planning a clinical trial for a time‐to‐event endpoint, we require an estimated effect size and need to consider the type of effect. Usually, an effect of proportional hazards is assumed with the hazard ratio as the corresponding effect measure.
Danzer MF, Dormuth I.
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A nonparametric test for comparing survival functions based on restricted distance correlation
Dependence Modeling, 2023 In this article, we propose an omnibus test for comparing two survival functions under non-proportional hazards. The test statistic is based on a product-limit estimate of the restricted distance correlation, which is closely related to the L2{L}_{2 ...
Zhang Qingyang
doaj +1 more source
BMC Research Notes, 2021 Objectives To examine the presence of the time-dependent effect of metronomic chemotherapy for the treatment of older patients with acute myeloid leukemia (AML) who were unfit for standard chemotherapy and to reanalyze the data using an appropriate ...
Phichayut Phinyo +2 more
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Non‐proportional hazards in immuno‐oncology: Is an old perspective needed? [PDF]
Pharmaceutical Statistics, 2020 AbstractA fundamental concept in two‐arm non‐parametric survival analysis is the comparison of observed versus expected numbers of events on one of the treatment arms (the choice of which arm is arbitrary), where the expectation is taken assuming that the true survival curves in the two arms are identical.
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Generating Survival Times to Simulate Cox Proportional Hazards Models [PDF]
, 2003 This paper discusses techniques to generate survival times for simulation studies regarding Cox proportional hazards models. In linear regression models, the response variable is directly connected with the considered covariates, the regression ...
Blettner, Maria +3 more
core +1 more source