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Working with Human Tissues for Translational Cancer Research

Working with Human Tissues for Translational Cancer Research

Published on: November 26, 2015

A note on tree gatekeeping procedures in clinical trials.

Alex Dmitrienko¹, Ajit C Tamhane, Lingyun Liu

¹Eli Lilly and Company, Indianapolis, IN 46285, USA. dmitrienko_alex@lilly.com

Statistics in Medicine

|May 20, 2008

Summary

This summary is machine-generated.

This study revises a tree gatekeeping procedure for hypothesis testing. It demonstrates that specific weight assignment algorithms can ensure gatekeeping and independence properties, correcting potential flaws in prior methods.

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Last Updated: Jul 5, 2026

Working with Human Tissues for Translational Cancer Research

Working with Human Tissues for Translational Cancer Research

Published on: November 26, 2015

Area of Science:

Statistics
Biostatistics

Background:

The Dmitrienko et al. tree gatekeeping procedure utilizes weighted Bonferroni tests within a closure method for hierarchically ordered hypotheses.
This procedure aims to maintain gatekeeping and independence properties crucial for valid statistical inference.

Discussion:

This note critically examines the weight assignment algorithm proposed by Dmitrienko et al., highlighting its potential failure to satisfy the monotonicity condition.
Violation of the monotonicity condition can compromise the gatekeeping property, leading to incorrect conclusions in hypothesis testing.

Key Insights:

Any weight assignment algorithm meeting a set of sufficient conditions can ensure the desired gatekeeping and independence properties.
The original Dmitrienko et al. algorithm may not always meet these conditions, necessitating a modification.
A revised algorithm is presented to address the monotonicity issue and guarantee the procedure's validity.

Outlook:

The findings provide a more robust framework for applying tree gatekeeping procedures in complex hierarchical testing scenarios.
This work contributes to the development of reliable statistical methods for multiple hypothesis testing.
Future research could explore the application of these modified procedures in various scientific fields requiring rigorous hypothesis validation.