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Sample size calculation for recurrent event data with additive rates models.

Liang Zhu¹, Yimei Li², Yongqiang Tang³

¹Neurology group, Eisai, Woodcliff Lake, New Jersey, USA.

Pharmaceutical Statistics

|July 26, 2021

Summary

This summary is machine-generated.

This study introduces new sample size calculation methods for recurrent event clinical trials, focusing on additive treatment effects. These methods offer practical advantages for superiority, non-inferiority, and equivalence trial designs.

Keywords:

additive rates models overdispersion recurrent event sample size calculation sandwich variance

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Area of Science:

Biostatistics
Clinical Trial Design
Epidemiology

Background:

Recurrent events are common primary endpoints in clinical trials.
Existing sample size calculation methods often assume multiplicative treatment effects.
Additive treatment effects offer more intuitive clinical interpretation.

Purpose of the Study:

To develop and investigate new methods for sample size calculation in recurrent event trials.
To focus on additive treatment effect models for superiority, non-inferiority, and equivalence trials.
To provide flexible methods accounting for various trial complexities.

Main Methods:

Development of novel sample size calculation methodologies based on the additive rates model.
Incorporation of flexible baseline rate functions, staggered entry, and random dropout.
Consideration of overdispersion in event counts.

Main Results:

Proposed methods perform well across diverse simulation settings.
The additive rates model provides a clinically meaningful alternative to multiplicative models.
The methods are applicable to superiority, non-inferiority, and equivalence trial designs.

Conclusions:

The presented methods offer a robust and practical approach to sample size calculation for recurrent event trials with additive treatment effects.
These methods enhance the design flexibility and interpretability of clinical trials.
Real-world data application demonstrates the utility of the proposed techniques.