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Published on: June 21, 2018
Multiplicity issues in exploratory subgroup analysis
Ilya Lipkovich1, Alex Dmitrienko2, Christoph Muysers3
1a QuintilesIMS, Advisory Analytics , Durham , NC , USA.
Abstract:
The general topic of subgroup identification has attracted much attention in the clinical trial literature due to its important role in the development of tailored therapies and personalized medicine. Subgroup search methods are commonly used in late-phase clinical trials to identify subsets of the trial population with certain desirable characteristics. Post-hoc or exploratory subgroup exploration has been criticized for being extremely unreliable. Principled approaches to exploratory subgroup analysis based on recent advances in machine learning and data mining have been developed to address this criticism. These approaches emphasize fundamental statistical principles, including the importance of performing multiplicity adjustments to account for selection bias inherent in subgroup search. This article provides a detailed review of multiplicity issues arising in exploratory subgroup analysis. Multiplicity corrections in the context of principled subgroup search will be illustrated using the family of SIDES (subgroup identification based on differential effect search) methods. A case study based on a Phase III oncology trial will be presented to discuss the details of subgroup search algorithms with resampling-based multiplicity adjustment procedures.
Insights
This study reviews methods for subgroup identification in clinical trials, emphasizing multiplicity adjustments to ensure reliability in personalized medicine. It highlights principled approaches like SIDES to address biases in exploratory subgroup analysis.
Area of Science:
- Clinical trial methodology
- Biostatistics
- Personalized medicine
Background:
- Subgroup identification is crucial for developing tailored therapies and personalized medicine.
- Exploratory subgroup analysis in clinical trials has faced criticism for unreliability.
- Advances in machine learning offer principled approaches to subgroup identification.
Purpose of the Study:
- To review multiplicity issues in exploratory subgroup analysis.
- To illustrate multiplicity corrections using SIDES methods.
- To present a case study of subgroup search in an oncology trial.
Main Methods:
- Review of multiplicity issues in exploratory subgroup analysis.
- Illustration of multiplicity corrections with SIDES (subgroup identification based on differential effect search) methods.
- Application of subgroup search algorithms with resampling-based multiplicity adjustments in a Phase III oncology trial.
Main Results:
- Principled subgroup search methods, incorporating multiplicity adjustments, enhance the reliability of exploratory analyses.
- SIDES methods provide a framework for addressing selection bias in subgroup identification.
- Resampling-based multiplicity adjustments are effective in subgroup search algorithms.
Conclusions:
- Addressing multiplicity is essential for robust subgroup identification in clinical trials.
- Principled subgroup search, like SIDES, improves the validity of personalized medicine approaches.
- The presented methods and case study offer practical guidance for reliable subgroup analysis.
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