Correlation between the genomic o454-nlpD region polymorphisms, virulence gene equipment and phylogenetic group of extraintestinal Escherichia coli (ExPEC) enables pathotyping irrespective of host, disease and source of isolation

Table 3 Strength of association between the o454-nlpD regions and the MLST and Ecor groups, class or pathotype, host species, clinical category, and serogroup

	*cramers.v*	*uc.RC*	*p.uc.RC*	*uc.CR*	*p.uc.CR*	*uc.sym*
MLST	0.99	0.28	0	0.99	0	0.44
Ecor	0.75	0.58	1.49e-228	0.72	4.63e-284	0.65
Class/Pathotype	0.22	0.05	2.79e-06	0.06	3.64e-06	0.05
Host species	0.31	0.08	1.42e-13	0.11	2.23e-11	0.09
Clinical category	0.19	0.03	1.38e-05	0.05	1.57e-05	0.04
O-groups	0.63	0.16	2.12e-65	0.45	1.8e-62	0.24
H-groups	0.56	0.17	1.48e-47	0.38	1.77e-42	0.24
Serogroup	0.84	0.19	8.93e-156	0.75	1.65e-272	0.3

The values Cramer’s V, uc.RC, p.uc.RC, uc.CR, p.uc.CR and uc.sym are reported here. Cramers.v measure the association between two nominal variables, giving a value between 0 and +1 (inclusive); uc.RC is the Theil’s symmetric Uncertainty Coefficient UC, indicating how much knowing the values of the Row variables decreases uncertainty about the Column variables; p.uc.RC is the probability of gaining UC(R|C) by chance; uc.CR is the Theil’s symmetric Uncertainty Coefficient UC, indicating how much knowing the values of the Column variables decreases uncertainty about the Row variables; p.uc.CR is the probability of gaining UC(C|R) by chance; uc.sym is a combination of uc.RC and uc.CR. The association was evaluated with the R-package ‘polytomous’. The two-way contingency tables used for this analysis are reported in Additional files (see Additional file 2, Additional file 5, Additional file 6, Additional file 7, Additional file 8 and Additional file 9).

ISSN: 1757-4749