Table 4.
Required sample size of eligible patients to achieve 90% power based on a one-sided 0.025 level test, assuming a mean of 15 eligible patients per cluster (N=26 total clusters).
| Intraclass Correlation Coefficient | Control Group Probability of Informed Choice | |||
|---|---|---|---|---|
| Intervention Group Probability of Informed Choice | ||||
| .2 | .25 | .3 | ||
| 0 | .05 | 228 | 155 | 110 |
| .1 | 572 | 292 | 184 | |
| .15 | 2504 | 708 | 348 | |
| 0.01 | .05 | 260 | 171 | 125 |
| .1 | 652 | 333 | 210 | |
| .15 | 2855 | 807 | 397 | |
| 0.02 | .05 | 292 | 192 | 141 |
| .1 | 732 | 374 | 236 | |
| .15 | 3205 | 906 | 445 | |
| 0.03 | .05 | 324 | 213 | 156 |
| .1 | 812 | 415 | 261 | |
| .15 | 3556 | 1005 | 494 | |
| 0.05 | .05 | 388 | 255 | 187 |
| .1 | 972 | 496 | 313 | |
| .15 | 4257 | 1204 | 592 | |