Table 5 Accuracy measures of biotin Streptavidin (BS) strip using PCR as a reference test in health care worker groups.

From: Modified streptavidin–biotin based lateral flow test strip for rapid detection of SARS-CoV-2 S1 antigen in saliva samples

 

Day

PCR (−)

strip (−)

PCR (+)

strip (+)

PPV (%)

NPV (%)

Accuracy (%)

Sensitivity (%)

Specificity (%)

kappa

Kappa SE

P-value

High risk group (n = 25)

4

16/17

9/8

100.00

94.10

96.0

88.9

100.00

0.911

0.087

0.000

6

14/15

11/10

100.00

93.30

96.0

90.9

100.00

0.918

0.08

0.000

Paramedic group (n = 20)

4

17/18

3/2

100.00

94.40

95.0

66.7

100.00

0.773

0.216

0.000

6

15/16

5/4

100.00

93.80

95.0

80.0

100.00

0.857

0.138

0.000

  1. PPV, positive predictive value; NPV, negative predictive value.
  2. P < 0.00 and P < 0.000: represent significant agreement.