64 citations · 79 across the 12 of their papers we have counts for
14 papers
Finite-sample correction for the covariate-adjusted log-rank test
Pavla Krotka, Dominic Magirr
The covariate-adjusted log-rank test is a novel method for covariate adjustment in randomized trials with time-to-event endpoints, offering guaranteed efficiency gains compared to…
Confidence intervals for two-stage adaptive designs with subpopulation selection
Enyu Li, Nigel Stallard, Ekkehard Glimm +2
We consider clinical trials in which an experimental treatment is compared with a control in pre-specified patient subpopulations. In such settings, adaptive enrichment designs all…
How to interpret hazard ratios
Jonathan W. Bartlett, Dominic Magirr, Tim P. Morris
The hazard ratio, typically estimated using Cox's famous proportional hazards model, is the most common effect measure used to describe the association or effect of a covariate on…
Robust modestly weighted log-rank tests
Dominic Magirr, Fredrik Öhrn
The introduction of checkpoint inhibitors in immuno-oncology has raised questions about the suitability of the log-rank test as the default primary analysis method in confirmatory…
Efficiency of nonparametric superiority tests based on restricted mean survival time versus the log-rank test under proportional hazards
Dominic Magirr, Craig Wang, Xinlei Deng +2
Background: For RCTs with time-to-event endpoints, proportional hazard (PH) models are typically used to estimate treatment effects and logrank tests are commonly used for hypothes…
Treatment-control comparisons in platform trials including non-concurrent controls
Marta Bofill Roig, Pavla Krotka, Katharina Hees +5
Shared controls in platform trials comprise concurrent and non-concurrent controls. For a given experimental arm, non-concurrent controls refer to data from patients allocated to t…
Visualizing hypothesis tests in survival analysis under anticipated delayed effects
José L. Jiménez, Isobel Barrott, Francesca Gasperoni +1
What can be considered an appropriate statistical method for the primary analysis of a randomized clinical trial (RCT) with a time-to-event endpoint when we anticipate non-proporti…
NCC: An R-package for analysis and simulation of platform trials with non-concurrent controls
Pavla Krotka, Katharina Hees, Peter Jacko +3
Platform trials evaluate the efficacy of multiple treatments, allowing for late entry of the experimental arms and enabling efficiency gains by sharing controls. The power of indiv…
Stratified modestly-weighted log-rank tests in settings with an anticipated delayed separation of survival curves
Dominic Magirr, José L. Jiménez
Delayed separation of survival curves is a common occurrence in confirmatory studies in immuno-oncology. Many novel statistical methods that aim to efficiently capture potential lo…
On model-based time trend adjustments in platform trials with non-concurrent controls
Marta Bofill Roig, Pavla Krotka, Carl-Fredrik Burman +9
Platform trials can evaluate the efficacy of several treatments compared to a control. The number of treatments is not fixed, as arms may be added or removed as the trial progresse…
Design and Analysis of group-sequential clinical trials based on a modestly-weighted log-rank test in anticipation of a delayed separation of survival curves: A practical guidance
Dominic Magirr, José L. Jiménez
A common feature of many recent trials evaluating the effects of immunotherapy on survival is that non-proportional hazards can be anticipated at the design stage. This raises the…
Non-proportional hazards in immuno-oncology: is an old perspective needed?
Dominic Magirr
A 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…
Modestly Weighted Logrank Tests
Dominic Magirr, Carl-Fredrik Burman
We propose a new class of weighted logrank tests (WLRT) that control the risk of concluding that a new drug is more efficacious than standard of care, when, in fact, it is uniforml…
Adaptive Survival Trials
Dominic Magirr, Thomas Jaki, Franz Koenig +1
Mid-study design modifications are becoming increasingly accepted in confirmatory clinical trials, so long as appropriate methods are applied such that error rates are controlled.…