TABLE 4.

Evaluation of confirmatory strategies

Standard and strategya	Value (%)b
	Sensitivity	Specificity	PPV	NPV	Costd	Coste	10% Prevalencec
							PPV	NPV	Costd	Coste
PGS
1	100.00	89.32	89.22	100.00	1.73	335.16	50.99	100.00	ND	ND
2	98.90	100.00	100.00	99.04	177.92	3,138.34	100.00	99.88	66.01	680.63
3	94.51	96.12	95.56	95.19	3.46	335.16	73.00	99.37	ND	ND
4	93.41	100.00	100.00	94.50	157.20	6,099.93	100.00	99.27	43.49	1,232.35
5	100.00	97.09	96.81	100.00	129.39	2,788.63	79.23	100.00	ND	ND
6	100.00	97.09	96.81	100.00	79.02	1,703.03	79.23	100.00	29.35	413.85
RGS
1	97.94	91.75	92.23	97.80		335.16	56.89	99.75	ND	ND
2	92.78	100.00	100.00	93.27		6,904.31	100.00	99.20	57.71	777.16
3	89.69	96.91	96.67	90.38		335.16	76.32	98.83	ND	ND
4	87.63	100.00	100.00	88.99		15,249.82	100.00	98.64	39.66	1,426.21
5	94.85	97.94	97.87	95.00		6,274.45	83.64	99.42	ND	ND
6	94.85	97.94	97.87	95.00		1,915.94	83.64	99.42	25.58	459.25

^aStrategies are as follows: 1, screening with Eu2 and confirming equivocal results with EuW; 2, screening with Eu2 and confirming all positive and equivocal results with EuW; 3, screening with Gu2 and confirming all equivocal results with EuW; 4, screening with Gu2 and confirming all positive and equivocal results with EuW; 5, screening with Eu2 and Gu2 in parallel and resolving all discordant results with EuW; 6, screening with Eu2, retesting all positive and equivocal results with Gu2, and resolving the remaining discordant results with EuW.

^bND, not determined.

^cAssuming a hypothetical 10% HSV-2 seroprevalence.

^dAdditional cost of the confirmatory strategy per sample relative to the cost of screening only; in the high-risk collective identical values are obtained for PGS and RGS.

^eAdditional cost of the confirmatory strategy per additional correctly diagnosed sample relative to the cost of screening only.