Table 3.

Final logistic regression model showing the effect of 3 variables on outcome with p values, ORs and CIs

Variable	Model adaptation criteria	Effect
	Likelihood log −2	χ2	df	P value	ORs	95% CIs
Age	70.390	6.325	2	0.042
≤30 days				0.041	3.051	0.928 to 10.036
31 days–1 year				0.066	0.406	0.021 to 1.415
>1 year				0.455	0.422	0.130 to 1.371
Case history	82.549	18.485	9	0.030
Neonatal calf diarrhoea				0.990	0.998	0.477 to 2.088
Calving				0.269	1.747	0.733 to 4.162
Administration of colostrum				0.598	1.372	0.483 to 3.900
Anorexia/asthenia				1.000	0.858	0.265 to 2.776
Postpartum disorders				0.028	1.080	0.112 to 10.450
Bovine respiratory disease				1.000	1.029	0.221 to 4.801
Dehorning/disbudding				1.000	0.686	0.061 to 7.776
Enteritis				1.000	1.372	0.084 to 22.464
Ruminal bloat				0.640	0.457	0.046 to 4.526
Other				0.315	0.412	0.026 to 1.625
Error	76.506	12.441	5	0.029
Improper administration of drugs				0.868	0.930	0.480 to 1.801
Forced extraction				0.179	0.588	0.212 to 0.966
Oral oesophageal tubing				0.035	1.922	0.411 to 3.560
Awkward use of a nipple bottle				0.862	0.961	0.343 to 2.694
Excessive thermal application				0.373	0.490	0.061 to 7.776
Other				0.998	1.372	0.266 to 7.079

The referent category of the dependent variable for the final logistic regression model is the outcome ‘recovery’.