Table 3

Positive and negative predictive values of HSV-2 test approaches by population prevalence

Positive Predictive Value


True Prevalence

Focus HSV-2 ELISA

Biokit

Focus HSV-2 ELISA+Biokit


10

61.9%

86.5%

89.8%

20

78.5%

93.5%

95.2%

30

86.3%

96.1%

97.1%

40

90.7%

97.5%

98.1%

50

93.6%

98.3%

98.8%

70

97.2%

99.3%

99.5%

90

99.2%

99.8%

99.9%

Negative Predictive Value

10

99.9%

98.9%

99.9%

20

99.8%

97.7%

99.8%

30

99.6%

96.0%

99.6%

40

99.4%

94.0%

99.4%

50

99.1%

91.2%

99.1%

70

98.0%

81.7%

97.9%

90

92.5%

53.6%

92.3%


Ranges indicated show the confidence intervals for accuracy; these also incorporate the uncertainty from having confirmed only a portion of Focus negatives. Biokit was used to confirm all sera that were initially positive for HSV-2 antibodies by Focus HSV-2 ELISA; the combined test results are shown in the "Focus Plus Biokit" column.

Morrow et al. BMC Infectious Diseases 2005 5:84   doi:10.1186/1471-2334-5-84

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