Table 2 Allocation ratios, overall power and sample size comparisons for the adding a treatment arm design using optimal allocation when treatments finish recruitment at different times
From: Designs for adding a treatment arm to an ongoing clinical trial
| Stage 3 ratio | Stage 2 ratio | n23 | Correlation | Overall power |
|---|---|---|---|---|
| 1:0.2 | 2.015:1:1 | 100 | 0.170 | 0.852 |
| 1:0.3 | 1.932:1:1 | 93 | 0.176 | 0.850 |
| 1:0.4 | 1.856:1:1 | 85 | 0.181 | 0.848 |
| 1:0.5 | 1.791:1:1 | 78 | 0.186 | 0.847 |
| 1:0.6 | 1.730:1:1 | 71 | 0.191 | 0.845 |
| 1:0.7 | 1.678:1:1 | 64 | 0.197 | 0.844 |
| 1:0.8 | 1.632:1:1 | 58 | 0.202 | 0.843 |