Table 2. Sample serum classification table using three-antigen Boolean classifier.

	Serum (+)	Serum (–)	Total	Serum (+) percentage
RNA(–)	7	16	23	30% (95% CI 11–48)
RNA(+) all intervals	76	20	96	79% (95% CI 71–97)
Total	83	36	119
Interval samples
RNA(+) < 10 days	9	16	25	36% (95% CI 17–54)
RNA(+) 10–20 days	53	16	69	77% (95% CI 67–87)
RNA(+) > 21 days	21	2	23	95% (95% CI 86–100)
Total	83	34	117 a

^aTime interval not available for two patients.