Find Minimum Sample Size for Target Detection Power

Determines the minimum subgroup sample size needed to achieve a target detection probability for a given true hazard ratio.

Usage

find_required_sample_size(
  theta,
  target_power = 0.8,
  prop_cens = 0.3,
  hr_threshold = 1.25,
  hr_consistency = 1,
  n_range = c(20L, 500L),
  tol = 1,
  verbose = TRUE
)

Arguments

theta

Numeric. True hazard ratio in subgroup.

target_power

Numeric. Target detection probability (0-1). Default: 0.80

prop_cens

Numeric. Proportion censored. Default: 0.3

hr_threshold

Numeric. HR threshold. Default: 1.25

hr_consistency

Numeric. HR consistency threshold. Default: 1.0

n_range

Integer vector of length 2. Range of sample sizes to search. Default: c(20, 500)

tol

Numeric. Tolerance for bisection search. Default: 1

verbose

Logical. Print progress. Default: TRUE

Value

A list with:

n_sg_required

Minimum sample size (rounded up)

achieved_power

Actual detection probability at n_sg_required

theta

Input hazard ratio

target_power

Input target power

Examples

if (FALSE) { # \dontrun{
# Find sample size for 80% power to detect HR = 1.5
result <- find_required_sample_size(
  theta = 1.5,
  target_power = 0.80,
  prop_cens = 0.2
)
print(result)
} # }