TABLE 2.

Sensitivity and specificity of the N3M-PCR assay on env, gag, and pol regions and on the three regions combined

HIV-1 gene region(s)	Result for infants aged:
	48 h		1-2 mo		3-6 mo
	Sensitivitya (n = 10)	Specificityb (n = 94)	Sensitivity (n = 12)	Specificity (n = 94)	Sensitivity (n = 16)	Specificity (n = 94)
env	40.0	100	91.7	98.9	87.5	100
gag	30.0	100	75.0	100	75.0	100
pol	50.0	100	66.7	100	87.5	98.9
Three regions combinedc	30.0	100	91.7	100	93.7	100

^aSensitivity is derived from the number of HIV-1-positive infants determined by the N3M-PCR assay divided by the number of HIV-1-positive infants determined by the validation standard.

^bSpecificity is derived from the number of HIV-1-negative infants determined by the N3M-PCR assay divided by the number of HIV-1-positive infants determined by the validation standard.

^cCombined results from all three regions were interpreted as follows: (i) if more than two regions of the pol, gag, and env genes were positive, the samples were determined to be HIV-1 positive; (ii) if only one region was positive, the results were reported as indeterminate for HIV-1; moreover, HIV-1 DNA samples determined to be indeterminate or positive were retested by the N3M-PCR assay; (iii) if none of the three regions was amplified, the samples were considered HIV-1 negative.