TABLE 3.

Sensitivity and specificity for the subset of tests performed by USPHLs in B. pertussis, B. parapertussis, B. holmesii, and B. pertussis/B. holmesii (undifferentiated)

Organism	Sample bacterial concn (CFU/ml)	na	Sensitivity (% [95% CI])	Specificity (% [95% CI])
B. pertussis	All	907	96.1 (93.2–97.9)	95.1 (93.2–96.8)
	1 × 103	170	88.4 (78.4–94.9)	89.1 (81.3–94.4)
	1 × 104	154	97.6 (87.1–99.9)	99.1 (95.2–100)
	1 × 105	312	97.4 (92.7–99.5)	96.9 (93.4–98.9)
	1 × 106	230	100 (90.3–100)	94.3 (90.1–97.1)
	1 × 107	41	100 (91.4–100)	—b
B. parapertussis	All	844	98.6 (95.9–99.7)	99.7 (98.9–100)
	1 × 103	170	97.1 (84.7–99.9)	99.3 (96.0–100)
	1 × 104	141	99.0 (94.8–100)	100 (90.3–100)
	1 × 105	284	—	99.6 (98.1–100)
	1 × 106	213	98.6 (92.7–100)	100 (97.4–100)
	1 × 107	36	—	100 (90.3–100)
B. holmesii	All	666	98.2 (94.7–99.6)	97.8 (96.1–98.9)
	1 × 103	130	96.2 (86.8–99.5)	98.7 (93.1–100)
	1 × 104	111	—	96.4 (91.0–99.0)
	1 × 105	227	100 (88.1–100)	97.5 (94.2–99.2)
	1 × 106	168	98.8 (93.5–100)	98.8 (93.6–100)
	1 × 107	30	—	100 (88.4–100)
B. pertussis/B. holmesii	All	330	97.6 (94.4–99.2)	96.0 (90.9–98.7)
	1 × 103	78	93.7 (84.5–98.2)	100 (78.2–100)
	1 × 104	52	100 (73.5–100)	95.0 (83.1–99.4)
	1 × 105	105	100 (93.5–100)	100 (92.9–100)
	1 × 106	83	100 (94.3–100)	85.0 (62.1–96.8)
	1 × 107	12	91.7 (61.5–99.8)	—

^an, number of tests reported for each organism, including tests of positive and negative samples.

^b—, incalculable values due to empty cells, e.g., no false negatives with 95% CI.