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Table 7

Binary logistic regression model showing prediction of total coliforms by tank features

Predictor Variables		B	S.E.	Sig.	Exp(B)	95% C.I. for Exp(B)
Tank type/material	Stainless steel tanks	−1.171	0.793	0.140	0.310	0.066	1.466
Tank type/material	Plastic tanks	−1.003	0.680	0.140	0.367	0.097	1.391
Tank connector	PPR connectors	−0.049	0.550	0.929	0.952	0.324	2.799
Tank age	Tank age 0 to 5 years	0.049	0.691	0.944	1.050	0.271	4.069
	Tank age 6 to 10 years	−0.133	0.676	0.845	0.876	0.233	3.296
	Constant	1.473	1.318	0.264	4.363
	Nagelkerke R Square=0.063
	Galvanised steel tanks, GI connectors, and tank age over 10 years were taken as the constant against which the other categories of the predictor variables were compared

Predictor Variables		B	S.E.	Sig.	Exp(B)	95% C.I. for Exp(B)
Tank type/material	Stainless steel tanks	−1.171	0.793	0.140	0.310	0.066	1.466
Tank type/material	Plastic tanks	−1.003	0.680	0.140	0.367	0.097	1.391
Tank connector	PPR connectors	−0.049	0.550	0.929	0.952	0.324	2.799
Tank age	Tank age 0 to 5 years	0.049	0.691	0.944	1.050	0.271	4.069
	Tank age 6 to 10 years	−0.133	0.676	0.845	0.876	0.233	3.296
	Constant	1.473	1.318	0.264	4.363
	Nagelkerke R Square=0.063
	Galvanised steel tanks, GI connectors, and tank age over 10 years were taken as the constant against which the other categories of the predictor variables were compared

Note: B, Intercept; S.E. Standard Error; Exp(B), Odds ratio.