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Sample sizes by study type.
| Study Type | n | Minimum | Sample Size Median | Maximum |
|---|---|---|---|---|
| RCT (no phase specified) | 27 | 64 | 550 | 2503 |
| RCT phase 2 | 3 | 200 | 2499 | 2648 |
| RCT phase 2b | 1 | 460 | ||
| RCT phase 3 | 9 | 312 | 802 | 1620 |
| RCT phase 3b | 2 | 716 | 730 | 744 |
| RCT phase 4 | 3 | 376 | 1341 | 1504 |
| Case Control | 1 | 590 | ||
| Prospective Observational Cohort | 1 | 530 | ||
| Retrospective Observational Cohort | 1 | 36,844 | ||
| Surveillance report | 1 | 128,297 | ||
| Case Reports | 1 | 833 |
