Two Stage

The TWOSTAGE program is a program that calculates:

  1. Estimates of sample size for a two-stage study.
  2. Rejection (R1) and Acceptance (A1) points for a two-stage trial.
  3. Power for an array of Pa compared to a fixed P0.

For further details, view the Help Document.


User Input
Program Output

Planned Design with Early Stopping for


Select Hypothesis Test Parameters

Null Proportion
Alternative Proportion
Alpha
Power



Sample Size
Stage 1
n1
Stage 2
n2

n1 or n2 may be changed


Acceptance Threshold
Rejection Threshold
Stage 1
a1
r1
Stage 2
a2
r2

a1, a2, or r1 may be changed


Futility
Efficacy
Correct
P(accept H0|P0)
P(reject H0|PA)
Incorrect
P(accept H0|PA)
P(reject H0|P0)

Alpha
Power

Power Alternative Proportion Prob(Early H0/Pa) Prob(Early HA/Pa)