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Comparison of included records by study design
| Study design | Number (%) |
|---|---|
| Cohort study | 39 (49%) |
| Literature review | 17 (21%) |
| Opinion | 8 (10%) |
| Case report | 5 (6%) |
| Case series | 4 (5%) |
| Cross-sectional study | 3 (4%) |
| Case–control | 1 (1%) |
| Systematic review | 1 (1%) |
| Survey | 1 (1%) |
| Textbook | 1 (1%) |
