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Summary of the articles used for this literature review and level of evidence
| Article type | Number | Level of evidence | ||||
|---|---|---|---|---|---|---|
| I | II | III | IV | V | ||
| Total | 65 | 6 | 26 | 12 | 6 | 15 |
| Original article | ||||||
| Epidemiological review | 7 | 5 | 2 | |||
| Prospective | 30 | 6 | 21 | 2 | 1 | |
| Retrospective | 13 | 8 | 5 | |||
| Literature review | 1 | 1 | ||||
| Expert opinion/background | 13 | 13 | ||||
| Author’s reply | 1 | 1 | ||||
