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Table 5

Kendall's Tau (KT) non-parametric correlation analysis based on concordant and discordant pairs of observations^a in pre- and post-disinfection effluent, five WWTPs, Ontario, 2014–2017

	F⁺ (male-specific) coliphage			Somatic coliphage
	KT value	p-value	Significance**	KT value	p-value	Significance**
Pre-disinfection
Norovirus GI	0.28	0.002	Yes	0.19	0.03	Yes
Norovirus GII	0.32	0.0004	Yes	0.28	0.002	Yes
Norovirus GI + GII	0.33	0.0003	Yes	0.26	0.004	Yes
Enterovirus culture	0.13	0.14	No	−0.05	0.5	No
Enterovirus RT-PCR	0.22	0.01	Yes	0.33	0.0003	Yes
Somatic coliphage	0.28	0.002	Yes
E. coli	0.47	2.7 × 10⁻⁷	Yes	0.095	0.3	No
Post-disinfection
Norovirus GI	0.26	0.004	Yes	0.22	0.01	Yes
Norovirus GII	0.18	0.04	Yes	0.13	0.1	No
Norovirus GI + GII	0.24	0.008	Yes	0.19	0.03	Yes
Enterovirus culture	0.29	0.001	Yes	0.32	0.0003	Yes
Enterovirus RT-PCR	0.22	0.01	Yes	0.22	0.01	Yes
Somatic coliphage	0.58	1 × 10⁻¹⁰	Yes
E. coli	0.43	1.6 × 10⁻⁶	Yes	0.3	0.0008	Yes

	F⁺ (male-specific) coliphage			Somatic coliphage
	KT value	p-value	Significance**	KT value	p-value	Significance**
Pre-disinfection
Norovirus GI	0.28	0.002	Yes	0.19	0.03	Yes
Norovirus GII	0.32	0.0004	Yes	0.28	0.002	Yes
Norovirus GI + GII	0.33	0.0003	Yes	0.26	0.004	Yes
Enterovirus culture	0.13	0.14	No	−0.05	0.5	No
Enterovirus RT-PCR	0.22	0.01	Yes	0.33	0.0003	Yes
Somatic coliphage	0.28	0.002	Yes
E. coli	0.47	2.7 × 10⁻⁷	Yes	0.095	0.3	No
Post-disinfection
Norovirus GI	0.26	0.004	Yes	0.22	0.01	Yes
Norovirus GII	0.18	0.04	Yes	0.13	0.1	No
Norovirus GI + GII	0.24	0.008	Yes	0.19	0.03	Yes
Enterovirus culture	0.29	0.001	Yes	0.32	0.0003	Yes
Enterovirus RT-PCR	0.22	0.01	Yes	0.22	0.01	Yes
Somatic coliphage	0.58	1 × 10⁻¹⁰	Yes
E. coli	0.43	1.6 × 10⁻⁶	Yes	0.3	0.0008	Yes

^aIn each sampling event, the concentration of F⁺ (male-specific) or somatic coliphage was compared with the concentration of each of the other microorganisms. Thus, for each microorganism in pre- or post-disinfection samples, there were 58 observation pairs (34 for secondary-treated + 24 tertiary-treated effluent) that were evaluated as concordant or discordant.

**Statistical significance given by p-value ≤0.05.

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