Table 5.

Risk factors for calf morbidity rate based on multivariable Cox regression analysis Table 5. Risk factors for calf morbidity rate based on multivariable Cox regression analysis

Variables	Category	HR	P >z	95% CI for HR
Calf age	< 3 mon	Ref
	>3 mon	0.22	<0.001	0.12 - 0.39
Calf sex	Male	Ref
	Female	0.57	0.018	0.36 - 0.91
Calving difficulty	No	Ref
	Yes	2.4	0.022	1.13 - 5.03
Dairy farming as a primary source of income	Yes	Ref
	No	1.7	0.029	1.05 - 2.65
Farmer’s education	No formal Edu	Ref
	Primary	0.61	0.184	0.30 - 1.26
	Secondary	0.26	0.007	0.10 - 0.69
	College	0.30	<0.001	0.16 - 0.58

Ref Reference, HR Hazard Ratio