Table 5. Accuracy of BD rapid influenza diagnostic tests (RIDTs) in different age groups.

BD Directigen Flu A+B test and BD Directigen EZ Flu A+B test	PCR negative	PCR positive	Prevalence % (95%CI)	Sensitivity % (95% CI)	Specificity % (95% CI)	PPV (%)	NPV (%)
<1
negative	49	16	38(27–50)	47(29–65)	100(91–100)	100(73–100)	75(63–85)
positive	0	14
n = 65
1–3
negative	232	120	49(44–53)	46(40–53)	99(96–100)	97(91–99)	66(61–71)
positive	3	104
n = 352
4–6
negative	151	140	64(60–68)	48(42–54)	99(96–100)	99(95–100)	51(46–58)
positive	1	128
n = 291
7–10
negative	126	173	70(66–75)	43(37–49)	98(94–100)	98(94–100)	42(37–48)
positive	2	130
n = 299
11–20
negative	185	133	55(50–60)	42(36–48)	100(97–100)	100(94–100)	58(52–64)
positive	0	97
n = 318
>20
negative	174	134	48(43–54)	18(12–25)	99(94–99)	97(81–100)	57(51–62)
positive	1	29
n = 308
Total
negative	917	716	57(55–59)	41(38–44)	99(98–100)	98(97–99)	56(54–59)
positive	7	502
n = 1633	925	1218

Key: CI—confidence interval

PPV—positive predictive value

NPV—negative predictive value