Product Manual

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Sofia Strep A FIA
Table 3a
Sofia Strep A FIA Results: READ NOW Mode
Table 3b
Sofia Strep A FIA Results: WALK AWAY Mode
Reproducibility Studies
The reproducibility of the Sofia Strep A FIA was evaluated at three (3) different laboratories. Two (2) different operators at
each site tested a series of coded, contrived samples, prepared in negative clinical matrix, ranging from low negative to
moderate positive Group A Streptococcus. The inter-laboratory agreement (Table 4) for negative samples was 96.7%-100%
and 96.7%-100% for positive samples. The intra-laboratory agreement (Table 5) for all samples ranged from 97.5%-99.2%.
Table 4
Sofia Strep A FIA Reproducibility Study Inter-laboratory Agreement
Table 5
Sofia Strep A FIA Reproducibility Study Intra-laboratory Agreement
Culture Sens. = 89.3% (100/112)
Pos Neg Total:
(95% CI: 82.2%-93.8%)
Sofia Pos 100 23 123 Spec. = 96.0% (549/572)
Sofia Neg 12 549 561
(95% CI: 94.0%-97.3%)
Total: 112 572 684 PPV = 81.3% (100/123)
NPV = 97.9% (549/561)
Prev. = 16.4% (112/684)
Culture Sens. = 100% (16/16)
Pos Neg Total:
(95% CI: 80.6%-100%)
Sofia Pos 16 1 17 Spec. = 97.2% (35/36)
Sofia Neg 0 35 35
(95% CI: 85.8%-99.5%)
Total: 16 36 52 PPV = 94.1% (16/17)
NPV = 100% (35/35)
Prev. = 30.8% (16/52)
Site
Low Negative (no bacteria)
(0 cfu/test)
High Negative (C 5 )
(1.5x10
3
cfu/test)
Low Positive (C 95 )
(3.0x10
3
cfu/test)
Mod. Positive (C 3X )
(2.8x10
4
cfu/test)
1 30/30 30/30 28/30 30/30
2 30/30 29/30 30/30 30/30
3 30/30 28/30 29/30 30/30
Total 90/90 87/90 87/90 90/90
% Overall Agreement
(95% CI)
100% (90/90)
(95.9%-100%)
96.7% (87/90)
(90.7%-98.9%)
96.7% (87/90)
(90.7%-98.9%)
100% (90/90)
(95.9%-100%)
Site
Low Negative (no bacteria)
(0 cfu/test)
High Negative (C 5 )
(1.5x10
3
cfu/test)
Low Positive (C 95 )
(3.0x10
3
cfu/test)
Mod. Positive (C 3X )
(2.8x10
4
cfu/test)
% Overall Agreement
(95% CI)
1 30/30 30/30 28/30 30/30
98.3% (118/120)
(94.1%-99.5%)
2 30/30 29/30 30/30 30/30
99.2% (119/120)
(95.4%-99.9%)
3 30/30 28/30 29/30 30/30
97.5% (117/120)
(92.9%-99.1%)