Calibrate k_inter for Target Subgroup Hazard Ratio

Finds the interaction effect multiplier (k_inter) that achieves a target hazard ratio in the harm subgroup.

Usage

calibrate_k_inter(
  target_hr_harm,
  model = "alt",
  k_treat = 1,
  cens_type = "weibull",
  k_inter_range = c(-100, 100),
  tol = 1e-06,
  use_ahr = FALSE,
  verbose = FALSE,
  ...
)

Arguments

target_hr_harm

Numeric. Target hazard ratio for the harm subgroup

model

Character. Model type ("alt" only). Default: "alt"

k_treat

Numeric. Treatment effect multiplier. Default: 1

cens_type

Character. Censoring type. Default: "weibull"

k_inter_range

Numeric vector of length 2. Search range for k_inter. Default: c(-100, 100)

tol

Numeric. Tolerance for root finding. Default: 1e-6

use_ahr

Logical. If TRUE, calibrate to AHR instead of Cox-based HR. Default: FALSE

verbose

Logical. Print diagnostic information. Default: FALSE

...

Additional arguments passed to create_gbsg_dgm

Value

Numeric value of k_inter that achieves the target HR

Details

This function uses uniroot to find the k_inter value such that the empirical HR (or AHR) in the harm subgroup equals target_hr_harm.

Examples

if (FALSE) { # \dontrun{
# Find k_inter for HR = 1.5 in harm subgroup
k <- calibrate_k_inter(target_hr_harm = 1.5, verbose = TRUE)

# Verify
dgm <- create_gbsg_dgm(model = "alt", k_inter = k, verbose = TRUE)
print(dgm$hr_H_true)  # Should be close to 1.5

# Calibrate to AHR instead
k_ahr <- calibrate_k_inter(target_hr_harm = 1.5, use_ahr = TRUE, verbose = TRUE)
dgm_ahr <- create_gbsg_dgm(model = "alt", k_inter = k_ahr, verbose = TRUE)
print(dgm_ahr$AHR_H_true)  # Should be close to 1.5
} # }