Table III.

Logistic regression comparing the association of Clostridium perfringens diagnosis and independent variables

Independent variables	Odds ratio	Standard error	95% Confidence interval	P-value
Average age of submitted piglets (d)	0.69	0.106	0.51–0.93	0.016
Seasona
Winter	Referent
Spring	0.13	0.116	0.024–0.73	0.021
Fall	0.13	0.108	0.028–0.65	0.013
ETEC detection
No	Referent
Yes	0.27	0.192	0.068–1.1	0.065
Yeara
2010	Referent
2002	0.074	0.0967	0.0059–0.94	0.045
2003	0.089	0.0956	0.011–0.73	0.025
2004	0.056	0.0713	0.0046–0.68	0.024
2005	0.19	0.163	0.037–1.0	0.052
2006	0.040	0.0500	0.0033–0.47	0.011
2007	0.078	0.0840	0.0095–0.64	0.018
2009	0.17	0.159	0.029–1.0	0.056

^aParameters for 2001 (no cases of C. perfringens diagnosed), 2008, and summer (P > 0.1) are not shown.

ETEC — enterotoxigenic E. coli.