TITLE:
Frequentist and Bayesian Sample Size Determination for Single-Arm Clinical Trials Based on a Binary Response Variable: A Shiny App to Implement Exact Methods
AUTHORS:
Susanna Gentile, Valeria Sambucini
KEYWORDS:
Binomial Proportion, Frequentist and Bayesian Power Functions, Exact Sample Size Determination, Shiny App, Two-Priors Approach
JOURNAL NAME:
Open Journal of Statistics,
Vol.14 No.1,
February
29,
2024
ABSTRACT: Sample size determination typically relies on a power
analysis based on a frequentist conditional approach. This latter can be seen
as a particular case of the two-priors approach, which allows to build four distinct power functions to select the optimal
sample size. We revise this approach when the focus is on testing a single
binomial proportion. We consider exact methods and introduce a conservative
criterion to account for the typical non-monotonic behavior of the power
functions, when dealing with discrete data. The main purpose of this paper is
to present a Shiny App providing a
user-friendly, interactive tool to apply these criteria. The app also provides
specific tools to elicit the analysis and the design prior
distributions, which are the core of the two-priors approach.