Table I.
Operating characteristics of two survival clinical trial designs with outcome-adaptive randomization.
| Proposed design using short-term response information |
Common design ignoring short-term response information |
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|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Four category | Four category | |||||||||||
| response rates | mean survival | Mean | Chance | Mean | Chance | |||||||
| # of | to be | # of | to be | |||||||||
| Arm | p1 | p2 | p3 | p4 | μ1 | μ2 | μ3 | μ4 | patients | selected | patients | selected |
| Scenario 1: A and B have the same CR/PR rates and durations | ||||||||||||
| A | 0.2 | 0.4 | 0.1 | 0.3 | 4 | 30 | 75 | 110 | 58 (50 per cent) | 0.046 | 59 (50 per cent) | 0.046 |
| B | 0.2 | 0.4 | 0.1 | 0.3 | 4 | 30 | 75 | 110 | 58 (50 per cent) | 0.048 | 59 (50 per cent) | 0.045 |
| Total: | 116 (100 per cent) | 118 (100 per cent) | ||||||||||
| Scenario 2: B has higher CR/PR rates, same CR/PR durations | ||||||||||||
| A | 0.2 | 0.4 | 0.1 | 0.3 | 4 | 30 | 75 | 110 | 16 (18 per cent) | 0.0002 | 26 (25 per cent) | 0.002 |
| B | 0.1 | 0.1 | 0.2 | 0.6 | 4 | 30 | 75 | 110 | 71 (82 per cent) | 0.590 | 77 (75 per cent) | 0.429 |
| Total: | 87 (100 per cent) | 103 (100 per cent) | ||||||||||
| Scenario 3: B has higher CR/PR rates, longer CR/PR durations | ||||||||||||
| A | 0.2 | 0.4 | 0.1 | 0.3 | 4 | 30 | 75 | 110 | 11 (18 per cent) | 0.0002 | 21 (29 per cent) | 0.001 |
| B | 0.1 | 0.1 | 0.2 | 0.6 | 6 | 45 | 112 | 165 | 51 (82 per cent) | 0.976 | 72 (71 per cent) | 0.648 |
| Total: | 62 (100 per cent) | 93 (100 per cent) | ||||||||||
| Using equal randomization for the first 30 patients | ||||||||||||
| Scenario 1: A and B have the same CR/PR rates and durations | ||||||||||||
| A | 0.2 | 0.4 | 0.1 | 0.3 | 4 | 30 | 75 | 110 | 58 (51 per cent) | 0.048 | 58 (50 per cent) | 0.047 |
| B | 0.2 | 0.4 | 0.1 | 0.3 | 4 | 30 | 75 | 110 | 56 (49 per cent) | 0.054 | 58 (50 per cent) | 0.047 |
| Total: | 114 (100 per cent) | 116 (100 per cent) | ||||||||||
| Scenario 2: B has higher CR/PR rates, same CR/PR durations | ||||||||||||
| A | 0.2 | 0.4 | 0.1 | 0.3 | 4 | 30 | 75 | 110 | 23 (31 per cent) | 0.0002 | 29 (29 per cent) | 0.004 |
| B | 0.1 | 0.1 | 0.2 | 0.6 | 4 | 30 | 75 | 110 | 52 (69 per cent) | 0.704 | 70 (71 per cent) | 0.477 |
| Total: | 75 (100 per cent) | 99 (100 per cent) | ||||||||||
| Scenario 3: B has higher CR/PR rates, longer CR/PR durations | ||||||||||||
| A | 0.2 | 0.4 | 0.1 | 0.3 | 4 | 30 | 75 | 110 | 20 (33 per cent) | 0.0002 | 22 (28 per cent) | 0.0004 |
| B | 0.1 | 0.1 | 0.2 | 0.6 | 6 | 45 | 112 | 165 | 40 (67 per cent) | 0.918 | 58 (82 per cent) | 0.832 |
| Total: | 60 (100 per cent) | 80 (100 per cent) | ||||||||||