The incubation period of COVID-19: a global meta-analysis of 53 studies and a Chinese observation study of 11 545 patients

Table 3 The incubation period of Coronavirus disease 2019 in the 11 545 patients and in the 218 patients

	11 545 patients		P	218 patients		P
	N (%)	Mean incubation period (95% CI)	P	N (%)	Mean incubation period (95% CI)	P
Total	11 545 (100%)	7.1 (7.0–7.2)		218 (100%)	6.8 (6.2–7.4)
Gender			0.603			0.145
Male	5814 (52.7%)	7.2 (7.0–7.4)		121 (56.3%)	6.3 (5.4–7.2)
Female	5215 (47.3%)	7.1 (6.9–7.3)		94 (43.7%)	7.5 (6.7–8.4)
Age, years			< 0.001			0.009
< 18	460 (4.4%)	8.6 (8.0–9.3)		6 (2.8%)	9.3 (5.3–16.3)
18–40	3789 (36.3%)	7.2 (7.0–7.4)		73 (34.1%)	7.7 (6.6–9.0)
41–60	4425 (42.3%)	7.1 (6.9–7.2)		98 (45.8%)	5.7 (4.9–6.6)
> 60	1777 (17.0%)	7.0 (6.6–7.3)		37 (17.3%)	8.0 (6.5–9.8)
The date of onset			0.319
Reported date of onset^a	7303 (63.2%)	7.1 (7.0–7.3)
Date of first treatment minus 2.5 days^b	2168 (18.8%)	7.0 (6.7–7.3)
Date of diagnosis minus 5.4 days^c	2074 (18.0%)	7.3 (7.0–7.6)

N, number; CI, Confidence interval
^aThe incubation period was estimated in 7 303 patients with the clear date of onset
^bThe incubation period was estimated in 2 168 patients using the date of first treatment to fill in the missing date of onset
^cThe incubation period was estimated in 2 074 patients using the date of diagnosis to fill in the missing date of onset

ISSN: 2049-9957