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Stopping boundaries
| Boundary | Value | Comment |
|---|---|---|
| Efficacy stopping boundary (α11) | 0 | No stopping for efficacy |
| Efficacy stopping boundary (β11) | 0.2 | Stop the trial for futility if less than stage-wise p value |
| Efficacy stopping boundary (α12) | 0.2250 | Stop trial for efficacy at the second stage or recalculate based on conditional power at first interim analysis |
