Table 3
Meta-analysis for SI of three variants of concern and their summary statistics.
| Variant | Number of SI estimates | Mean | 95% CI | I 2 | Cochran’s Q | Egger |
|---|---|---|---|---|---|---|
| Alpha | 75 | 5.17 | 4.87 – 5.47 | 97.10 | 2026* | 0.58 |
| Delta | 8 | 4.07 | 3.03 – 5.10 | 99.10 | 700* | < 0.0001 |
| Omicron | 7 | 3.06 | 2.76 – 3.37 | 83.04 | 30.88* | 0.22 |
*P-value < 0.0001. SI: Serial interval; 95% CI: 95% confidence interval; I2: I-square or index of heterogeneity statistic; Cochran’s Q: Cochran’s Q heterogeneity statistic; Egger: Egger’s test for publication bias.