Table 5. Subgroup analyses.
| Subgroups comparison | Studies (N) | Pooled prevalence (%) | 95% confidence interval (%) |
|---|---|---|---|
| Average age, P=0.665 | |||
| Less than 50 y-old | 17 | 71.15 | 58.58–81.13 |
| Over 50 y-old | 5 | 63.76 | 29.79–87.95 |
| Country, P=0.711 | |||
| China | 20 | 70.08 | 57.30–80.34 |
| Italy | 2 | 62.33 | 22.31–90.51 |
| Region, P=0.755 | |||
| Hubei | 5 | 66.35 | 42.33–84.12 |
| Outside Hubei | 17 | 70.37 | 55.97–81.61 |
| Sample size, P=0.183 | |||
| Larger than 50 | 14 | 74.61 | 62.68–83.72 |
| Smaller than 50 | 8 | 57.24 | 32.68–78.68 |
| VES distribution, P=0.031* | |||
| VES inside the lesion area | 9 | 80.33 | 68.79–88.32 |
| VES inside and outside the lesion area | 13 | 59.51 | 42.33–74.64 |
| Slice thickness, P=0.963 | |||
| (0,1] mm | 7 | 71.52 | 47.55–87.43 |
| (1,3] mm | 2 | 64.73 | 23.02–91.84 |
| Greater than 3 mm | 10 | 67.33 | 47.67–82.34 |
| Varied within [0.625, 5] mm | 3 | 75.37 | 39.00–93.61 |
P values denoted the comparison between subgroups sorted by each moderator. *, indicates a significant P value. VES, vascular enlargement sign; y-old, year old.