Prevalence and Risk Factors of Bovine and Ovine Lungworm Infection at Durame District, Southern Ethiopia

Table 1

Method of calculating sensitivity, specificity, PPV, and NPV.

Techniques	Gold standard (necropsy)
Modified Baermann	Positive	Negative	Total
Positive	a	b	a/a+b (PPV)
Negative	c	d	d/c+d (NPV)
Total	a+c	b+d
	a/a+c (sensitivity)	d/b+d (specificity)