pFstop {BDP2}

Operating characteristics of a single-arm trial with a binary endpoint with futility stopping

Description

Determines the operating characteristics of a single-arm trial with a binary endpoint (success - failure) on the basis of analytical derivations. The design allows for futility stopping. Outputs are

• probability of futility stopping (P.futil) at each interim analysis

• cumulative stopping probability up to the interim (P.futil.cum).

Usage

pFstop(p, vn.int, v.crit)

Arguments

p

true response rate

vn.int

vector of sample sizes at the interim analyses

v.crit

vector of critical boundaries for futility stopping at the interim analyses (stop for futility if number of successes <= boundary). Choose boundary=-1 if no stopping is allowed.

Examples

pFstop(p=0.3,vn.int=c(3,9,13,18,20),v.crit=c(0,1,2,3,3))