Table 4.

CRP Values in Subjects Reporting Symptoms of Airway Infection in the Last 7 Days, on the Examination Day (n = 770), and by the Duration of Symptoms (n = 778)

	CRP
	n	Mean	Geometric mean	p value
Do you have symptoms of airway infection on the examination day?
Yes	260	6.0	2.8	0.002
No	510	4.7	2.1
Duration of the symptoms
≤7 days	333	6.6	2.8	<0.001a
8–14 days	250	4.1	2.1
15–21 days	89	5.0	2.1
≥22 days	106	2.9	1.8

^aSignificance of trend (Jonckhere–Terpstra test)