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Sample Size and Power Calculations
| Control Failure Rate | 30% |
| Bracing Failure Rate | 15% |
| Significance Level | 0.05 |
| Sample Size | 348 |
| Sample Size Adjusted for 10% drop-out | 384 |
| Percent of subjects in braced group | Power |
| 25% | 0.82 |
| 40% | 0.91 |
| 50% | 0.92 |
| 60% | 0.91 |
| 75% | 0.85 |
