Table 2.
Univariate association between characteristics of COVID-19 cases and incubation periods and serial intervals
| Incubation period | Serial interval | |||||
|---|---|---|---|---|---|---|
| Cases (n = 178) | Median (IQR) | P value* | Secondary cases (n = 131) | Median (IQR) | P value* | |
| Sex | 0.848 | 0.900 | ||||
| Female | 89 | 6 (4, 9) | 73 | 5 (2, 8) | ||
| Male | 89 | 6 (4, 9) | 58 | 4 (1.25, 9) | ||
| Age (years) | 0.054 | 0.358 | ||||
| <14 | 3 | 8 (7, 8.5) | 10 | 1 (1, 5.25) | ||
| 14–34 | 43 | 5 (3, 7.5) | 24 | 5 (2, 6) | ||
| 35–64 | 17 | 6 (4, 9) | 75 | 5 (2, 9) | ||
| >64 | 25 | 9 (6, 11) | 22 | 4 (2, 9.5) | ||
| Source of infection | 0.009 | 0.952 | ||||
| Wuhan-imported | 42 | 5 (2, 7.75) | 8 | 4.5 (2.75, 7.5) | ||
| Contact Wuhan cases | 99 | 6 (4, 9) | 68 | 4 (1, 11) | ||
| Locally infected | 37 | 7 (5,10) | 55 | 4 (2, 8.5) | ||
*P values were obtained from Wilcoxon rank sum test for sex, and Kruskal–Wallis test for age and source of infection.