Number of patients per treatment arm necessary to perform parallel grouped placebo-controlled clinical trialsa
| % Decrease in Mean Number of Enhancing Lesions | No. |
|---|---|
| 50 | 129 |
| 60 | 80 |
| 70 | 47 |
| 80 | 28 |
| 90 | 12 |
↵a To detect a percentage decrease in the mean number of enhancing lesions ranging from 50% to 90%, for a power of 80%.