gsrsb (version 1.2.1)

ldNominalSig: Calculate Nominal Significance, Error Spending Approach

Description

Nominal significance for the secondary endpoint are calculated by using the error spending approach.

Usage

ldNominalSig(alpha, tVec, cvec, locPeak, type = 2, initIntvl = c(1, 4))

Value

nominal significance of the secondary group sequential boundary.

Arguments

alpha

original significance level.

tVec

information vector.

cvec

primary group sequential boundary.

locPeak

location of maximum, a number between 1 and the number of interims.

type

O'Brien- Fleming (OBF) type error spending funciton is 1, Pocock (POC) type error spending funciton is 2.

initIntvl

computing paramter, a pair of numbers containing the end-points of the interval to be searched for the root.

Author

Jiangtao Gou

Details

This function calculates the nominal significance level of any Lan-DeMets error spending boundary. The original significance level is used to choose the initial searching range of the nominal significance.

References

Lan, K. K. G., and Demets, D. L. (1983). Discrete sequential boundaries for clinical trials. Biometrika 70, 659-663.

Tamhane, A. C., Gou, J., Jennison, C., Mehta, C. R., and Curto, T. (2018). A gatekeeping procedure to test a primary and a secondary endpoint in a group sequential design with multiple interim looks. Biometrics, 74, 40-48.

See Also

nominalSig, secondaryBoundaryVecLD

Examples

if (FALSE) {
require(mvtnorm)
require(ldbounds)
K <- 6;
tVec <- c(140,328,453,578,659,1080)/1080;
alpha <- 0.025;
cvec.obf <- ldbounds::ldBounds(t=tVec,iuse=c(1),alpha=c(alpha),sides = 1);
cvec <- cvec.obf$upper.bounds;
alphaprime <- ldNominalSig(alpha,tVec,cvec,locPeak=4,type=2,
      initIntvl=c(1,4))
}