TABLE 2.

Comparison of serotyping results and concordance for 140 S. pneumoniae from six ICS laboratories

ICS QC laboratory	Number of isolates testeda	Concordance by antisera available at each laboratoryb		Concordance by pool
		Number of correct results	Percent concordance	Number of correct results	Percent concordance
A	140	138	98.6	139	99.3
B	140	136	97.1	139	99.3
C	119	119	100	119	100
D	134	124	92.5	131	97.8
E	140	133	95.0	140	100
F	138	136	98.6	137	99.3
Total	811	786	96.9	805	99.3

^a Number of tested isolates varied due to non-viable isolates following shipping, and laboratory C not participating until the 2010B distribution.

^b Participants D and F maintain antisera that permit grouping and factoring for the most common serogroups.