Augmenting the logrank test in the design of clinical trials in which non-proportional hazards of the treatment effect may be anticipated [PDF]
BMC Medical Research Methodology, 2016 Background Most randomized controlled trials with a time-to-event outcome are designed assuming proportional hazards (PH) of the treatment effect. The sample size calculation is based on a logrank test.
Patrick Royston, Mahesh K.B. Parmar
doaj +10 more sources
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 ...
Jiménez JL.
europepmc +8 more sources
An approach to trial design and analysis in the era of non-proportional hazards of the treatment effect. [PDF]
Trials, 2014 Background: Most randomized controlled trials with a time-to-event outcome are designed and analysed under the proportional hazards assumption, with a target hazard ratio for the treatment effect in mind. However, the hazards may be non-proportional.
Royston P, Parmar MK.
europepmc +8 more sources
Methods for non-proportional hazards in clinical trials: A systematic review [PDF]
Statistical Methods in Medical Research, 2023 For 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.
Maximilian Bardo +15 more
semanticscholar +7 more sources
Mathematical Biosciences and Engineering, 2023 Many tests for comparing survival curves have been proposed over the last decades. There are two branches, one based on weighted log-rank statistics and other based on weighted Kaplan-Meier statistics.
María del Carmen Pardo, Beatriz Cobo
doaj +3 more sources
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.
Begun A, Kulinskaya E, Ncube N.
europepmc +5 more sources
Using fractional polynomials and restricted cubic splines to model non-proportional hazards or time-varying covariate effects in the Cox regression model. [PDF]
Stat Med, 2022 The Cox proportional hazards model is used extensively in clinical and epidemiological research. A key assumption of this model is that of proportional hazards.
Austin PC, Fang J, Lee DS.
europepmc +3 more sources
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 IntroductionAmong patients with acute myeloid leukemia (AML), the DACO-016 randomized study showed reduction in mortality for decitabine [Dacogen® (DAC), Eisai Inc., Woodcliff Lake, NJ, USA] compared with treatment choice (TC): at primary analysis the ...
Tomeczkowski J +7 more
europepmc +3 more sources
Group sequential design for time-to-event outcome with non-proportional hazards using the concept of relative time utilizing two different Weibull distributions [PDF]
Contemporary Clinical Trials CommunicationsA group sequential design allows investigators to sequentially monitor efficacy and safety as part of interim testing in phase III trials. Literature is well developed in the case of continuous and binary outcomes, however, in case of trials with a time ...
Milind A. Phadnis +2 more
doaj +3 more sources
Comparison of statistical methods for the analysis of recurrent adverse events in the presence of non-proportional hazards and unobserved heterogeneity: a simulation study [PDF]
BMC Medical Research Methodology, 2022 Background In preventive drug trials such as intermittent preventive treatment for malaria prevention during pregnancy (IPTp), where there is repeated treatment administration, recurrence of adverse events (AEs) is expected.
Noel Patson +6 more
doaj +4 more sources