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Number of clusters and consent by study size.
| Number of participants | Number of studies | Median number of clusters (IQR) | % of studies reporting participant and/or their proxy consent |
|---|---|---|---|
| <150 | 49 | 6 (3–12) | 84% |
| 150–350 | 48 | 15 (8–21) | 96% |
| 351–999 | 54 | 14(12–21) | 78% |
| ≥1000 | 36 | 38 (20–58) | 31% |
IQR—interquartile range.
