ph2simon: Simon's 2-stage Phase II design

Description

Calculates Optimal and Minimax 2-stage Phase II designs given by Richard Simon

Usage

ph2simon(pu, pa, ep1, ep2, nmax=100)
# S3 method for ph2simon
print(x, …)
# S3 method for ph2simon
plot(x, …)

Arguments

unacceptable response rate

response rate that is desirable

ep1

threshold for the probability of declaring drug desirable under p0

ep2

threshold for the probability of rejecting the drug under p1

nmax

maximum total sample size (default 100; can be at most 500)

object returned by ph2simon

...

arguments to be passed onto plot and print commands called within

Value

ph2simon returns a list with pu, pa, alpha, beta and nmax as above and:

out

matrix of best 2 stage designs for each value of total sample size n. the 6 columns are: r1, n1, r, n, EN(p0), PET(p0)

Trial is stopped early if <= r1 responses are seen in the first stage and treatment is considered desirable only when >r responses seen.

The "print" method formats and returns the minimax and optimal designs. The "plot" plots the expected sample size agains the maximum sample size as in Jung et al., 2001

References

Simon R. (1989). Optimal Two-Stage Designs for Phase II Clinical Trials. Controlled Clinical Trials 10, 1-10.

Jung SH, Carey M and Kim KM. (2001). Graphical Search for Two-Stage Designs for Phase II Clinical Trials. Controlled Clinical Trials 22, 367-372.

Examples

Run this code

# NOT RUN {
  ph2simon(0.2, 0.4, 0.1, 0.1)
  ph2simon(0.2, 0.35, 0.05, 0.05)
  ph2simon(0.2, 0.35, 0.05, 0.05, nmax=150)
# }