curtail: Generic function that calculates the probability to declare...

In seqmon: Group Sequential Design Class for Clinical Trials

Description

Calculates the probability to declare efficacy at the end of study given the Z value at the current look

Usage

curtail(lower.boundary,upper.boundary,look,t,noncen,current=lower.boundary[look])

Arguments

lower.boundary	lower boundaries
upper.boundary	upper boundaries
look	current look number
t	time of looks
noncen	noncentrality parameter
current	current Z statistic

Value

numeric

Examples

t<-c(0.33,0.67,1)
f<- function(t) 0.025*t^4
g<-function(t) 0.20*t^3
a<-f(t)
b<-g(t)
noncen<-pnorm(0.975)+pnorm(0.8)
curtail(b,a,1,t,noncen)

seqmon documentation built on Sept. 5, 2020, 1:06 a.m.