TABLE 1.

Reassignment of serotype-specific antibody titers to the international reference standard, lot 89SF, for 12 Pn serotypes

PnPs serotype	Titer (μg/ml) ± 95% CI for 89SF		Titer (μg/ml) (95% CI) for Giebink serac (CPS + Pn25 + Pn72)
	CPSa	CPS + Pn25 + Pn72b
1	6.32 ± 0.85	3.43 ± 0.45	4.78 (3.21, 7.11)
3	2.36 ± 0.30	0.53 ± 0.10	3.64 (3.18, 4.16)
4	4.07 ± 0.47	3.95 ± 0.50	6.38 (5.92, 6.88)
6B	16.87 ± 2.77	18.28 ± 2.70	7.88 (7.25, 8.58)
7F	5.21 ± 1.25	3.45 ± 0.60	10.2 (9.26, 11.3)
8	5.15 ± 0.88	6.42 ± 0.91	4.50 (3.41, 5.96)
9V	6.90 ± 1.85	6.93 ± 1.64	26.6 (21.9, 32.2)
12F	1.75 ± 0.39	1.69 ± 0.19	4.24 (3.66, 4.90)
14	27.76 ± 3.65	21.46 ± 3.90	9.02 (7.12, 11.4)
18C	4.46 ± 0.94	6.50 ± 1.57	8.97 (8.27, 9.74)
19F	12.97 ± 2.67	11.39 ± 2.92	10.0 (8.10, 12.3)
23F	8.14 ± 1.07	7.28 ± 1.05	6.41 (5.91, 6.95)

^aValues were obtained from the work of Quataert et al. (12, 13).

^b89SF was used only as an assay control.

^cGiebink sera listed by Ps type in Materials and Methods. CI, confidence interval.