TABLE 1.

Specificities and positive predictive values of the Architect HIV Ag/Ab combination assaya

ParameterValue(s) for assay group
MaleFemaleTotal
Total no. tested77,70877,631155,339
No. of positive initial screening test results (%)342 (0.440)201 (0.259)543 (0.350)
    No. of false-positive results (%)153 (0.197)193 (0.249)346 (0.223)
    No. of indeterminate results (%)4 (0.005)0 (0.000)4 (0.003)
    No. of true HIV-positive results (%)152 (0.196)5 (0.006)157 (0.101)
    No. of previously confirmed HIV-positive results (%)33 (0.042)3 (0.004)36 (0.023)
Specificity (%)99.8099.7599.78
    95% confidence interval (%)99.77-99.8399.71-99.7999.75-99.80
Positive predictive value (%)49.842.5331.21
    95% confidence interval (%)44.09-55.590.83-5.8027.22-35.49
  • a Tests with indeterminate results and previously HIV-confirmed samples were excluded in statistical analysis.