TABLE 2.

Relatedness of isolates in refined collections from the different geographical locales^a

Region	Avg. SAB for total collection	Avg. SAB for refined collection	% Isolates in refined collection in clusters for which SABs were as follows:
			≥0.80	≥0.90
NE	0.77 ± 0.09	0.74 ± 0.08	77	27
SE	0.71 ± 0.09	0.68 ± 0.08	65	8
MW	0.67 ± 0.10	0.67 ± 0.09	61	14
SW	0.76 ± 0.09	0.70 ± 0.08	39	22

^aIn the refinement process all but one member of isolates from a single hospital in each cluster (defined by an S_AB of ≥0.80) were removed from each collection.