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Table 11 Stopping Boundaries for Z Statistics and P-values

From: Statistical design of Phase II/III clinical trials for testing therapeutic interventions in COVID-19 patients

Stopping Boundaries for Z Statistics and P-values

 

Z at 1st Interim

P at 1st Interim

Z at 1st Futility

P at 1st Futility

Z at 2nd Interim

P at 2nd Interim

Z at 2nd Futility

P at 2nd Futility

Final Z

Final P

Intermediate Risk Group

 For Design with 1 Interim Analysis

2.539

0.006

−0.571

0.716

NA

NA

NA

NA

1.673

0.047

 For Design with 2 Interim Analyses

2.902

0.002

−0.954

0.830

2.199

0.014

0.530

0.298

1.689

0.046

High Risk Group

 For Design with 1 Interim Analysis

−2.539

0.006

0.571

0.716

NA

NA

NA

NA

−1.673

0.047

 For Design with 2 Interim Analyses

−2.902

0.002

0.954

0.830

−2.199

0.014

−0.530

0.298

−1.689

0.046

  1. All values were calculated based on 90% power