Results 51 to 60 of about 617,984 (298)

Weighted Cox Regression Using the R Package coxphw

Journal of Statistical Software, 2018
Cox's regression model for the analysis of survival data relies on the proportional hazards assumption. However, this assumption is often violated in practice and as a consequence the average relative risk may be under- or overestimated.
Daniela Dunkler, Meinhard Ploner, Michael Schemper, Georg Heinze   +3 more
doaj   +1 more source

Time and dose dependency of bone-sarcomas in patients injected with radium-224 [PDF]

, 1988
The time course and dose dependency of the incidence of bone-sarcomas among 900 German patients treated with high doses of radium-224 is analysed in terms of a proportional hazards model with a log-normal dependency of time to tumor and a linear ...
A. M. Kellerer, C. E. Land, C. W. Mays, CE Land, Committee on the biological effects of ionizing radiations, CW Mays, CW Mays, CW Mays, CW Mays, D Chmelevsky, D. Chmelevsky, H Spiess, H. Spiess, JS Spratt, RR Wick   +14 more
core   +1 more source

Treating non-responders: pitfalls and implications for cancer immunotherapy trial design

Journal of Hematology & Oncology, 2020
Background Conventional trial design and analysis strategies fail to address the typical challenge of immune-oncology (IO) studies: only a limited percentage of treated patients respond to the experimental treatment.
Zhenzhen Xu, Yongsoek Park, Ke Liu, Bin Zhu   +3 more
doaj   +1 more source

Which test for crossing survival curves? A user’s guideline

BMC Medical Research Methodology, 2022
Background The exchange of knowledge between statisticians developing new methodology and clinicians, reviewers or authors applying them is fundamental. This is specifically true for clinical trials with time-to-event endpoints.
Ina Dormuth, Tiantian Liu, Jin Xu, Menggang Yu, Markus Pauly, Marc Ditzhaus   +5 more
doaj   +1 more source

Partially linear censored quantile regression [PDF]

, 2009
Censored regression quantile (CRQ) methods provide a powerful and flexible approach to the analysis of censored survival data when standard linear models are felt to be appropriate.
B Honore, JL Powell, K Doksum, L Peng, L Tian, M Buchinsky, R Koenker, R Koenker, R Koenker, RJ Gray, S Portnoy, Stephen Portnoy, T Neocleous, Tereza Neocleous, V Chernozhukov, X He, X He, X He   +17 more
core   +1 more source

Estimation of treatment effects in weighted log-rank tests

Contemporary Clinical Trials Communications, 2017
Non-proportional hazards have been observed in clinical trials. The log-rank test loses power and the standard Cox model generally produces biased estimates under such conditions.
Ray S. Lin, Larry F. León
doaj   +1 more source

Effect of surgical treatment on patients with stage T3 or T4 triple-negative breast cancer: a SEER-based retrospective observational study

Frontiers in Endocrinology, 2023
BackgroundThe use of surgery is controversial in patients with stage T3 or T4 triple-negative breast cancer (TNBC). We aimed to explore the effect of surgical treatment on overall survival (OS) of these patients.MethodsA total of 2,041 patients were ...
Jie Hu, Changling Dai, Yang Zhang, Weijun Chen, Lihua Sun, Xu Zhang, Minjie Duan, Hao Fu, Teng Long, Wei Kang, Chengliang Yin, Xiaozhu Liu, Jie Yu   +12 more
doaj   +1 more source

An exact corrected log-likelihood function for Cox's proportional hazards model under measurement error and some extensions [PDF]

, 2002
This paper studies Cox`s proportional hazards model under covariate measurement error. Nakamura`s (1990) methodology of corrected log-likelihood will be applied to the so called Breslow likelihood, which is, in the absence of measurement error ...
Augustin, Thomas
core   +1 more source

A modified weighted log-rank test for confirmatory trials with a high proportion of treatment switching [PDF]

, 2020
In confirmatory cancer clinical trials, overall survival (OS) is normally a primary endpoint in the intention-to-treat (ITT) analysis under regulatory standards. After the tumor progresses, it is common that patients allocated to the control group switch
Bore, Alexander, Burman, Carl-Fredrik, Jiménez, José L., Niewczas, Julia   +3 more
core   +2 more sources

A novel design for randomized immuno-oncology clinical trials with potentially delayed treatment effects

Contemporary Clinical Trials Communications, 2015
The semi-parametric proportional hazards model is widely adopted in randomized clinical trials with time-to-event outcomes, and the log-rank test is frequently used to detect a potential treatment effect.
Pei He, Zheng Su
doaj   +1 more source