Table 4.
Sample size for composite outcome in main trial, estimated event rates – see text for data sources.
| Composite model | A | B | Ci | Cii | D |
|---|---|---|---|---|---|
| Composite outcome for Phase III includes: | MACE, dementia, non-vasc death, new MR signs | MACE, dementia, death | MACE, cog↓, dependency↓, death | MACE, cog imp, depend, all death | |
| 1-Beta (power) | 80% | 80% | 80% | 80% | 80% |
| Event rate, control, pa | 50% | 10% | 30% | 30% | 45% |
| Relative risk reduction | 20% | 20% | 20% | 30% | 20% |
| Event rate, active, pa | 40% | 8% | 24% | 21% | 36% |
| Total sample size | 950 | 6626 | 1784 | 778 | 976 |
| Total trial size, inc losses | 1250 | 7400 | 2000 | 900 | 1100 |
Assume: 1:1 randomisation and Fleiss adjustment; alpha 5%; primary outcome incomplete in 10%.
MACE: major adverse cardiovascular events; MR: magnetic resonance.