Table 3. Combination assay screening to identify HIV infection recency for the 130 and 180-day cut-offs periods.

	Sensitivity level	Relative False- Recency Rate	95% Lower bound	95% Upper bound
BED+PwD	75	28.3	13.8	47.9
130-day	80	35.0	17.0	48.3
cut-off	85	36.7	19.4	52.1
	90	40.0	23.2	68.5
BED+PwD	75	28.9	11.8	44.6
180-day	80	31.1	13.8	46.2
cut-off	85	31.1	18.1	53.2
	90	42.2	21.1	62.8
LAg+PwD	75	44.0	25.0	68.2
130-day	80	48.0	28.6	68.4
cut-off	85	48.0	27.5	73.3
	90	48.0	30.9	87.5
LAg+PwD	75	42.1	15.8	71.8
180-day	80	42.1	17.4	73.3
cut-off	85	42.1	18.5	71.8
	90	47.4	22.2	83.3

The table shows the reduction in the relative false-recency rate (rFRR) of the BED and LAg assays due to the PwD assay. A BED = 0.8 or LAg = 1.5 threshold was first used to screen the specimens for HIV infection recency. Specimens classified as recent were then re-screened using the PwD assay in order to reduce the rFRR while maintaining a 75%, 80%, 85% or 90% true-recency rate (sensitivity) of the BED or LAg assay. Since we are interested in the reduction of the rFRR by the PwD assay, we subtract this estimate from 100%. The results can be interpreted as follows: for the 180-day cut-off, the PwD assay reduces the rFRR by (100–42.2 =) 57.8% while maintaining a BED sensitivity of 90%. The table also gives the 95% confidence bounds for the reduction in the rFRR. The same result can be interpreted as follows: for the 180-day cut-off, the PwD assay reduces the rFRR by at least (100–62.8 =) 37.2% while maintaining a BED sensitivity of 90%.