Simulation of minimisation — simulate

simulate_mini repeatedly generates random data and then minimises with different specified burnin periods and/or minimisation probabilities. Its purpose is to guide decisions when designing a randomisation strategy for a randomised controlled trial.

Usage

simulate_mini(
  sampsize,
  factors,
  Nsims = 100,
  groups = 3,
  burnin,
  minprob,
  ratio = rep(1, groups)
)

Arguments

sampsize: the desired sample size of the data, i.e., the sample size of your prospective trial.
factors: a list of factors, each a list containing two items. The first is levels which is either a vector of the level names OR the number of levels. The second item is either props, a vector of proportions equal to the number of levels in the factor; OR prop.dist which is a named vector containing the mean and sd of the proportions.
Nsims: an integer, the number of simulations to run per scenario, default is 100.
groups: an integer, the number of groups to randomise, default is 3.
burnin: a vector of integers of possible burnin lengths before minimisation kicks in. Individual values must be > 0 and < total sample size.
minprob: a vector of the possible minimisation probabilities.
ratio: a numeric vector of randomisation ratios (must be of length equal to the number of groups).

Examples

simulate_mini(sampsize = 150,
              factors = list(sex = list(levels = c("M", "F"),
                                        props = c(0.5, 0.5)),
                             site = list(levels = 12,
                                         prop.dist = c(mean = 0.1, sd = 0.05))),
              Nsims = 10, groups = 3, burnin = c(10, 15),
              minprob = c(0.7, 0.8, 0.9), ratio = c(1,1,1))
#> Simulation of Multi-arm Minimisation 
#> --------------------------------------------------------------------------------
#> Number of simulations per scenario: 10 
#> Factors: sex, site 
#> Burnin options: 10, 15 
#> Minimisation probability options: 0.7, 0.8, 0.9 
#> Average group sizes:
#> | burnin| minprob|    A|    B|    C|
#> |------:|-------:|----:|----:|----:|
#> |     10|     0.7| 50.1| 49.6| 50.3|
#> |     15|     0.7| 49.2| 50.6| 50.2|
#> |     10|     0.8| 50.5| 49.4| 50.1|
#> |     15|     0.8| 50.2| 50.0| 49.8|
#> |     10|     0.9| 50.3| 49.9| 49.8|
#> |     15|     0.9| 50.5| 49.6| 49.9|
#> Average imbalance:
#> | burnin| minprob| imbalance|
#> |------:|-------:|---------:|
#> |     10|     0.7|      12.9|
#> |     15|     0.7|      12.2|
#> |     10|     0.8|       9.7|
#> |     15|     0.8|      10.4|
#> |     10|     0.9|       8.2|
#> |     15|     0.9|       8.9|