Table 1.

The clinical characteristics of the study cohort

Items	Patients (n = 50)	Nucleic acid positive (n = 31)	Nucleic acid false negative (n = 19)	P value
Age (y)	34 (25–42)	35 (25–44)	31 (25–38)	.542
<18	8 (16%)	4 (12.9%)	4 (21.05%)	.595
19‐40	28 (56%)	17 (54.8%)	11 (57.9%)
>40	14 (28%)	10 (32.3%)	4 (21.05%)
Sex
Male	17 (34%)	13 (41.9%)	4 (21.1%)	.218
Female	33 (66%)	18 (58.1%)	15 (78.9%)
Clinical type
Mild COVID‐19	10 (20%)	8 (25.8%)	2 (10.1%)	.282
Moderate COVID‐19	40 (80%)	23 (74.2%)	17 (89.5%)
Exposure history
Yes	36 (72%)	26 (83.9%)	10 (52.6%)	.025
No	14 (28%)	5 (16.1%)	9 (47.4%)
Chronic underlying disease
Chronic lung disease	4 (8%)	2 (6.5%)	2 (10.5%)	.629
High blood pressure	1 (2%)	0 (0%)	1 (5.3%)	.38
Postoperative tumor	2 (4%)	2 (6.5%)	0 (0%)	.519
Diabetes	1 (2%)	1 (3.2%)	0 (0%)	1
Chronic kidney disease	1 (2%)	0 (0%)	1 (5.3%)	.38
Allergic rhinitis	2 (4%)	0 (0%)	2 (10.5%)	.14
Hyperlipidemia	1 (2%)	1 (3.2%)	0 (0%)	1
Total number of patients with comorbidities	12 (24%)	6 (19.4%)	6 (31.6%)	.496
Signs and symptoms
Fever	33 (66%)	19 (61.3%)	14 (73.7%)	.540
Cough	35 (70%)	22 (71.0%)	13 (68.4%)	1
Expectoration	4 (8%)	2 (6.5%)	2 (10.5.%)	.629
Sore throat	13 (26%)	5 (16.1%)	8 (42.1%)	.54
Chest pain, Chest distress, breathlessness	11 (22%)	10 (32.3%)	1 (5.3%)	.035
Muscle aches	5 (10%)	2 (6.5%)	3 (15.8%)	.355
Fatigue	3 (6%)	2 (6.5%)	1 (5.3%)	1
Gastrointestinal symptoms	4 (8%)	4 (12.9%)	0 (0%)	.284
Headache and dizziness	5 (10%)	3 (5.9%)	2 (10.5%)	1
Chills	3 (6%)	1 (3.2%)	2 (10.5%)	.549
Runny nose	3 (6%)	1 (3.2%)	2 (10.5%)	.549
Time interval from symptom onset to first visit (d)	2 (1, 4)	2 (1, 4)	1 (1, 3.5)	.926
Clinical remission time (d)	12.5 (10, 16)	15 (11, 18.5)	10 (8, 13)	.005
Hospitalization days (d)	19.5 (15, 24)	23 (18, 27)	15 (13, 18)	P < .001