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Group Sequential Test for Two-Sample Ordinal Outcome Measures
Yuan Wu1, Ryan A Simmons2, Baoshan Zhang1
1Department of Biostatistics and Bioinformatics, Duke University, Durham NC, USA.
Statistics in Medicine
|March 17, 2025
Summary
This study introduces a new group sequential trial design for ordinal data using the Mann-Whitney-Wilcoxon test. This method enhances early decision-making in clinical trials, improving efficiency and patient safety.
Area of Science:
- Biostatistics
- Clinical Trial Design
- Statistical Methods
Background:
- Group sequential trials allow early efficacy or futility decisions.
- Existing methods are established for continuous, binary, and time-to-event data.
- Ordinal data analysis in sequential trials requires novel approaches.
Purpose of the Study:
- To propose a novel group sequential design for two-sample ordinal data.
- To utilize the Mann-Whitney-Wilcoxon test within a sequential framework.
- To provide a robust method for early clinical trial decision-making with ordinal outcomes.
Main Methods:
- Development of a group sequential design based on the Mann-Whitney-Wilcoxon test.
- Establishment of asymptotic normality for the test statistic.
- Verification of sequential statistics' adherence to Brownian motion assumptions.
- Finite sample simulation studies.
Main Results:
- The proposed test statistic demonstrates asymptotic normality.
- Sequential statistics align with Brownian motion assumptions.
- Simulations show superior Type I error control and maintained power compared to existing methods, especially for small sample sizes.
Conclusions:
- The proposed group sequential design is effective for ordinal data.
- This method offers advantages in Type I error control and power for clinical trials.
- The approach facilitates efficient trial design and early decision-making.
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