build_dtl_norm: Build a multi-stage drop-the-losers multi-arm clinical trial...

In mjg211/multiarm: Design of single- and multi-stage multi-arm clinical trials

Build a multi-stage drop-the-losers multi-arm clinical trial for a normally distributed primary outcome

Description

build_dtl_norm() builds a multi-stage drop-the-losers multi-arm clinical trial design object assuming the primary outcome variable is normally distributed, like those returned by des_dtl_norm.

Usage

build_dtl_norm(
  n1 = 147,
  n10 = 49,
  e = 2.17,
  Kv = c(2, 1),
  alpha = 0.025,
  beta = 0.1,
  delta1 = 0.5,
  delta0 = 0,
  sigma = 1,
  ratio = 1,
  power = "marginal",
  type = "variable",
  summary = FALSE
)

Arguments

n1	A numeric indicating the chosen value for n1, the total sample size required in stage one of the trial. Defaults to 147.
n10	A numeric indicating the chosen value for n10, the sample size required in the control arm in stage one of the trial. Defaults to 49.
e	A numeric indicating the chosen value for e, the critical rejection boundary for the final analysis. Defaults to 2.17.
Kv	A numeric vector of strictly decreasing values, indicating the chosen value for K, the number of experimental treatment arms present in each stage. Defaults to c(2, 1).
alpha	A numeric indicating the chosen value for α, the significance level (family-wise error-rate). Defaults to 0.025.
beta	A numeric indicating the chosen value for β, used in the definition of the desired power. Defaults to 0.1.
delta1	A numeric indicating the chosen value for δ1, the 'interesting' treatment effect. Defaults to 0.5.
delta0	A numeric indicating the chosen value for δ0, the 'uninteresting' treatment effect. Defaults to 0.
sigma	A numeric vector indicating the chosen values for σ0 and σ1, the standard deviations of the responses in the control and experimental arms. Must be of length 1 or 2. If of length 1, it is assumed that σ0 =σ1. Defaults to 1.
ratio	A numeric indicating the chosen value for r, the stage-wise allocation ratio to present experimental arms. Defaults to 1.
power	A character string indicating the chosen type of power to design the trial for. Can be "disjunctive" or "marginal". Defaults to "marginal".
type	A character string indicating the choice for the stage-wise sample size. Can be "variable" or "fixed". Defaults to "variable".
summary	A logical variable indicating whether a summary of the function's progress should be printed to the console. Defaults to FALSE.

Value

A list, with additional class "multiarm_des_dtl_norm", containing the following elements:

• A tibble in the slot $opchar summarising the operating characteristics of the identified design.

• A numeric in the slot $maxN specifying N, the trial's total required sample size.

• A numeric in the slot $n_factor, for internal use in other functions.

• Each of the input variables.

See Also

des_dtl_norm, gui, opchar_dtl_norm, plot.multiarm_des_dtl_norm, sim_dtl_norm.

Examples

# The design for the default parameters
des <- build_dtl_norm()

mjg211/multiarm documentation built on Jan. 19, 2024, 8:21 a.m.