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Group sequential design power using MaxCombo test under non-proportional hazards

Usage

gs_power_combo(
  enroll_rate = define_enroll_rate(duration = 12, rate = 500/12),
  fail_rate = define_fail_rate(duration = c(4, 100), fail_rate = log(2)/15, hr = c(1,
    0.6), dropout_rate = 0.001),
  fh_test = rbind(data.frame(rho = 0, gamma = 0, tau = -1, test = 1, analysis = 1:3,
    analysis_time = c(12, 24, 36)), data.frame(rho = c(0, 0.5), gamma = 0.5, tau = -1,
    test = 2:3, analysis = 3, analysis_time = 36)),
  ratio = 1,
  binding = FALSE,
  upper = gs_b,
  upar = c(3, 2, 1),
  lower = gs_b,
  lpar = c(-1, 0, 1),
  algorithm = GenzBretz(maxpts = 1e+05, abseps = 1e-05),
  ...
)

Arguments

enroll_rate

Enrollment rates.

fail_rate

Failure and dropout rates.

fh_test

A data frame to summarize the test in each analysis. See examples for its data structure.

ratio

Experimental:Control randomization ratio (not yet implemented).

binding

Indicator of whether futility bound is binding; default of FALSE is recommended.

upper

Function to compute upper bound.

upar

Parameters passed to upper.

lower

Function to compute lower bound.

lpar

Parameters passed to lower.

algorithm

an object of class GenzBretz, Miwa or TVPACK specifying both the algorithm to be used as well as the associated hyper parameters.

...

Additional parameters passed to mvtnorm::pmvnorm.

Value

A list with input parameters, enrollment rate, analysis, and bound.

Specification

The contents of this section are shown in PDF user manual only.

Examples

library(dplyr)
library(mvtnorm)
library(gsDesign)
library(gsDesign2)

enroll_rate <- define_enroll_rate(
  duration = 12,
  rate = 500 / 12
)

fail_rate <- define_fail_rate(
  duration = c(4, 100),
  fail_rate = log(2) / 15, # median survival 15 month
  hr = c(1, .6),
  dropout_rate = 0.001
)

fh_test <- rbind(
  data.frame(rho = 0, gamma = 0, tau = -1, test = 1, analysis = 1:3, analysis_time = c(12, 24, 36)),
  data.frame(rho = c(0, 0.5), gamma = 0.5, tau = -1, test = 2:3, analysis = 3, analysis_time = 36)
)

# Example 1 ----
# Minimal Information Fraction derived bound
# \donttest{
gs_power_combo(
  enroll_rate = enroll_rate,
  fail_rate = fail_rate,
  fh_test = fh_test,
  upper = gs_spending_combo,
  upar = list(sf = gsDesign::sfLDOF, total_spend = 0.025),
  lower = gs_spending_combo,
  lpar = list(sf = gsDesign::sfLDOF, total_spend = 0.2)
)
#> $enroll_rate
#> # A tibble: 1 × 3
#>   stratum duration  rate
#>   <chr>      <dbl> <dbl>
#> 1 All           12  41.7
#> 
#> $fail_rate
#> # A tibble: 2 × 5
#>   stratum duration fail_rate dropout_rate    hr
#>   <chr>      <dbl>     <dbl>        <dbl> <dbl>
#> 1 All            4    0.0462        0.001   1  
#> 2 All          100    0.0462        0.001   0.6
#> 
#> $bound
#>   analysis bound  probability probability0         z    nominal p
#> 1        1 upper 6.329275e-08 3.299865e-10  6.175397 3.299865e-10
#> 2        1 lower 3.269613e-04 0.000000e+00 -2.516527 9.940741e-01
#> 3        2 upper 4.260145e-01 2.565830e-03  2.798651 2.565830e-03
#> 4        2 lower 8.468664e-02 0.000000e+00  1.237721 1.079098e-01
#> 5        3 upper 9.015980e-01 2.500822e-02  2.097499 1.797473e-02
#> 6        3 lower 2.000038e-01 0.000000e+00  2.958921 1.543591e-03
#> 
#> $analysis
#>   analysis time        n    event event_frac       ahr
#> 1        1   12 500.0001 107.3943  0.3241690 0.8418858
#> 2        2   24 500.0001 246.2834  0.7434051 0.7164215
#> 3        3   36 500.0001 331.2910  1.0000000 0.6831740
#> 
#> attr(,"class")
#> [1] "non_binding" "combo"       "gs_design"   "list"       
# }