|
Placebo event rate
|
NI margin, absolute risk difference TXA vs. placebob
|
Power
|
Sample sizec
|
|---|
| |
0.90
|
8,868
|
|
10%a
|
1.18%
|
0.95
|
10,963
|
| |
0.97
|
12,441
|
|
0.90
|
8,078
|
|
11%a
|
1.29%
|
0.95
|
9,990
|
| |
0.97
|
11,340
|
|
0.90
|
7,390
|
|
12%a
|
1.39%
|
0.95
|
9,136
|
| |
0.97
|
10,367
|
- NI non-inferiority margin, TXA tranexamic acid
- aThe estimates are based on the event rates observed in the POISE-2 trial (aspirin-placebo group) [5] and in a simulated subpopulation of the VISION cohort [1, 2] matching the POISE-3 inclusion criteria
- bThese are the NI margins expressed as absolute risk differences, corresponding to a NI margin expressed as hazard ratio of 1.125, when the placebo event rate is 10%, 11%, or 12%
- cThese sample sizes are obtained from non-inferiority test for two survival curves using Cox’s proportional hazard model, with a hazard ratio of 1.125 as non-inferiority margin, and a hazard ratio of 0.9 as actual hazard ratio (one-sided test, alpha of 0.025)
