Table 3. Syphilis POC test sensitivity and specificity (compared to reference Treponemal immunoassay), overall and by HIV status and CD4 cell count.

			Determine		Onsite		DPP (Trep)		Bioline
		N	Sens	Spec	Sens	Spec	Sens	Spec	Sens	Spec
		(IA+/IA−)*	(95% CI)	(95% CI)	(95% CI)	(95% CI)	(95% CI)	(95% CI)	(95% CI)	(95% CI)
Overall		1203	97.3	96.4	92.5	97.0	89.8	98.3	87.8	98.5
		(736/467)	(95.8–98.3)	(94.1–97.8)	(90.3–94.3)	(94.9–98.3)	(87.3–91.9)	(96.5–99.2)	(85.1–90.0)	(96.8–99.3)
HIV status	Neg	724	95.9	97.8	91.2	97.2	89.8	98.6	86.5	98.9
		(364/360)	(93.1–97.6)	(95.5–99.0)	(87.7–93.8)	(94.8–98.6)	(86.1–92.7)	(96.6–99.5)	(82.5–89.8)	(97.0–99.6)
	Pos	154	96.9	81.5	94.5	85.2	89.8	88.9	87.4	88.9
		(127/27)	(91.6–99.0)	(61.3–93.0)	(88.6–97.6)	(65.4–95.1)	(82.8–94.2)	(69.7–97.1)	(80.1–92.4)	(69.7–97.1)
CD 4 count	<500	67	94.6	91.7	90.9	100.0	89.1	100.0	81.8	100.0
(cells/mm3)		(55/12)	(84.0–98.6)	(59.8–99.6)	(79.3–96.6)	(69.9–100.0)	(77.1–95.5)	(70.0–100.0)	(68.6–90.5)	(69.9–100)
	≥500	63	98.0	76.9	96.0	76.9	88.0	84.6	92.0	84.6
		(50/13)	(88.0–99.9)	(46.0–93.8)	(85.1–99.3)	(46.0–93.8)	(75.0–95.0)	(53.7–97.3)	(79.9–97.4)	(53.7–97.3)

*IA+/IA-  =  Treponemal immunoassay reactive/Treponemal immunoassay nonreactive.

Sens  =  sensitivity; Spec  =  specificity; SYD = Sydney (Architect Syphilis Chemiluminescence IA); MEL = Melbourne (Trepanostika TP recombinant Enzyme IA)

Differences between estimates were considered to be statistically significant where 95% CI were not overlapping.