Title: Calculate Regional Consistency Probabilities for Multi-Regional Clinical Trials
Version: 1.0.0
Description: Provides methods to calculate approximate regional consistency probabilities using Method 1 and Method 2 proposed by the Japanese Ministry of Health, Labor and Welfare (2007) https://www.pmda.go.jp/files/000153265.pdf. These methods are useful for assessing regional consistency in multi-regional clinical trials. The package can calculate unconditional, joint, and conditional regional consistency probabilities. For technical details, please see Homma (2024) <doi:10.1002/pst.2358>.
License: MIT + file LICENSE
Imports: mvtnorm, stats
Suggests: testthat (≥ 3.0.0)
Config/testthat/edition: 3
Encoding: UTF-8
RoxygenNote: 7.3.2
NeedsCompilation: no
Packaged: 2025-05-13 12:27:59 UTC; i_lik
Author: Gosuke Homma [aut, cre]
Maintainer: Gosuke Homma <my.name.is.gosuke@gmail.com>
Repository: CRAN
Date/Publication: 2025-05-15 14:00:06 UTC

Calculate Regional Consistency Probabilities

Description

This function calculates approximate regional consistency probabilities using Methods 1 and 2 proposed by Japanese MHLW (2007). The function can obtain:

For technical details, please see Homma (2024)

Usage

regional.consistency.probs(f.s, PI, alpha, power, seed)

Arguments

f.s

A numeric vector representing the proportion of patients in region s(=1,...,S) among patients in the entire trial population. Values must sum to 1.

PI

A numeric value specifying the threshold for Method 1 (typically set at 0.5).

alpha

A numeric value representing the one-sided level of significance.

power

A numeric value representing the target power.

seed

A random number seed.

Value

A list containing the following components:

f.s

The input proportion of patients in each region

PI

The input threshold value for Method 1

alpha

The input one-sided significance level

power

The input target power

seed

The input seed number

Uncond.Method1

Unconditional regional consistency probability for Method 1

Joint.Method1

Joint regional consistency probability for Method 1

Cond.Method1

Conditional regional consistency probability for Method 1

Uncond.Method2

Unconditional regional consistency probability for Method 2

Joint.Method2

Joint regional consistency probability for Method 2

Cond.Method2

Conditional regional consistency probability for Method 2

Examples

regional.consistency.probs(
  f.s = c(0.1, 0.45, 0.45),
  PI = 0.5,
  alpha = 0.025,
  power = 0.8,
  seed = 123
)