Table 3.
List of study endpoints with minimum detectable differences at 80% power, based on estimates of variability in outcome changes from pilot studies.
| Endpoint | Standard deviation of changes from pilot study | Minimum detectable difference (80% power) |
|---|---|---|
| Primary Outcome | ||
| F2-isoprostanes (pg/ml) | 40 | 12.6 |
| Secondary Outcomes Estrogensa: | ||
| Estradiol | 6 | 1.8 |
| Estrone | 15 | 4.6 |
| Estriol | 10 | 3.2 |
| 16-hydroxyestrone | 11 | 3.5 |
| 2-hydroxyestrone | 5 | 1.6 |
| 2-hydroxyestradiol | 1.004291 | 0.315347 |
| 2-hydroxyestrogens combined | 6.416084 | 2.01465 |
| 4-Hydroxyestrone | 0.462954 | 0.145367 |
| 4-hydroxyestradiol | 5.205566 | 1.634548 |
| 4-hydroxyestrogens combined | 0.898837 | 0.282235 |
| 2-Methyhydroxyestrone | 2.712885 | 0.851846 |
| 2-methyhydroxyestradiol | 18.06073 | 5.671068 |
| 2/16 hydroxyestrone ratio | 0.511265 | 0.160537 |
| 4/2 hydroxyestrogens ratio | 0.108517 | 0.034074 |
| Body composition variables: | ||
| BMI (kg/m2) | 1.593873 | 0.500476 |
| %Body fat (by DXA scan) | 2.296699 | 0.721164 |
| Insulin and Glucose: | ||
| Insulin (mU/L) | 1.800009 | 0.565203 |
| Glucose (mg/dL) | 6.849493 | 2.150741 |
| Insulin resistance index (HOMA) | 0.5432 | 0.170565 |
| Insulin resistance ln (HOMA) | 0.384855 | 0.120845 |
| IGF proteins: | ||
| IGF-I (ng/ml) | 43.10523 | 13.53504 |
| IGFBP-1 (ng/ml) | 22.44738 | 7.048477 |
| IGFBP-2 (ng/ml) (from WTBS) | 99.70928 | 31.30871 |
| IGFBP-3 (ng/ml) | 367.35 | 115.3479 |