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The articles classified according to methodology
| Study design | Number of articles |
|---|---|
| Prospective, multicenter | 4 |
| Prospective | 4 |
| Retrospective | 48 |
| Retrospective, multicenter | 13 |
| Retrospective review of prospective database | 5 |
| Retrospective review of prospective database, multicenter | 5 |
