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Studies characteristics
| Parameter | Results |
|---|---|
| Study type: | |
| Observational | 64 |
| Randomized clinical trial | 11 |
| Systematic review | 8 |
| Review | 5 |
| Review/expert opinion | 4 |
| Case series | 3 |
| Meta-analysis | 2 |
| Basic science | 1 |
| Case report | 1 |
| Clinical guidelines | 1 |
| Funding source: | |
| Neither | 79 |
| Public foundations | 18 |
| Commercial companies | 2 |
| Both | 1 |
