twoCoprimary (version 1.0.0)

twoCoprimary2BinaryApprox: Unified Interface for Two Co-Primary Binary Endpoints (Approximate Methods)

Description

This function provides a unified interface for both power calculation and sample size determination for two co-primary binary endpoints using asymptotic normal approximation methods.

Usage

twoCoprimary2BinaryApprox(
  n1 = NULL,
  n2 = NULL,
  p11,
  p12,
  p21,
  p22,
  rho1,
  rho2,
  power = NULL,
  r = NULL,
  alpha = 0.025,
  Test = "AN"
)

Value

An object of class "twoCoprimary" containing either:

• Power calculation results (when n1 and n2 are specified)

• Sample size calculation results (when power and r are specified)

Arguments

n1

Sample size for group 1 (treatment group). If NULL, will be calculated.

n2

Sample size for group 2 (control group). If NULL, will be calculated.

p11

True response probability for endpoint 1 in group 1

p12

True response probability for endpoint 2 in group 1

p21

True response probability for endpoint 1 in group 2

p22

True response probability for endpoint 2 in group 2

rho1

Correlation between endpoints 1 and 2 in group 1

rho2

Correlation between endpoints 1 and 2 in group 2

power

Target power (1 - beta). If NULL, will be calculated.

r

Allocation ratio (n1/n2). Required when calculating sample size.

alpha

One-sided significance level (typically 0.025 or 0.05)

Test

Test method: "AN" (asymptotic normal), "ANc" (with continuity correction), "AS" (arcsine), or "ASc" (arcsine with continuity correction)

Details

This function serves as a unified interface similar to power.prop.test(). The function determines the operation mode based on which parameters are NULL.

Exactly one of {(n1, n2), (power, r)} must be NULL.

Examples

# Calculate power given sample sizes
twoCoprimary2BinaryApprox(
  n1 = 200, n2 = 100,
  p11 = 0.5, p12 = 0.4,
  p21 = 0.3, p22 = 0.2,
  rho1 = 0.7, rho2 = 0.7,
  alpha = 0.025, Test = "AN"
)

# Calculate sample size given target power
twoCoprimary2BinaryApprox(
  p11 = 0.5, p12 = 0.4,
  p21 = 0.3, p22 = 0.2,
  rho1 = 0.7, rho2 = 0.7,
  power = 0.8, r = 1,
  alpha = 0.025, Test = "AN"
)