Group-sequential designs are a sub-class of the TwoStageDesign
class with constant stage-two sample size.
See TwoStageDesign
for slot details.
Any group-sequential design can be converted to a fully flexible
TwoStageDesign
(see examples section).
Usage
GroupSequentialDesign(n1, c1f, c1e, n2_pivots, c2_pivots, order = NULL, ...)
# S4 method for GroupSequentialDesign
TwoStageDesign(n1, ...)
Arguments
- n1
stage one sample size or
GroupSequentialDesign
object to convert (overloaded fromTwoStageDesign
)- c1f
early futility stopping boundary
- c1e
early efficacy stopping boundary
- n2_pivots
numeric of length one, stage-two sample size
- c2_pivots
numeric vector, stage-two critical values on the integration pivot points
- order
of the Gaussian uadrature rule to use for integration, set to length(c2_pivots) if NULL, otherwise first value of c2_pivots is repeated 'order'-times.
- ...
further optional arguments
See also
TwoStageDesign
for superclass and inherited methods
Examples
design <- GroupSequentialDesign(25, 0, 2, 25, c(1, 1.5, 2.5))
summary(design)
#> GroupSequentialDesign: n1 = 25
#>
futility | continue | efficacy
#>
x1: -0.00 | 0.23 1.00 1.77 | 2.00
#>
c2(x1): +Inf | +1.00 +1.50 +2.50 | -Inf
#>
n2(x1): 0 | 25 25 25 | 0
#>
TwoStageDesign(design)
#> TwoStageDesign<n1=25;0.0<=x1<=2.0:n2=25>