Leica Biosystems Bond Oracle HER2 IHC System User Manual
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Leica Biosystems Bond Oracle HER2 IHC System Instructions for Use TA9145 EN-CE-Rev_E 18/06/2013
English
2x2 Concordance Results
In this primary analysis the test results from the two tests (Bond Oracle HER2 IHC System
and Dako HercepTest) are categorized as negative (0,1+) or positive (2+, 3+). The frequencies
of four possible combinations are displayed in a 2x2 table format (see Table 6). Then, the
overall concordance rate based on this 2x2 table was calculated accompanied by a 95% exact
confidence interval (based on the binomial distribution).
The null hypothesis (H
0
), which the success criteria are set against, is that concordance is no
greater than 75%.
The observed agreement for 431 samples between the two tests in a 2x2 analysis show a
concordance of 92.34% (398/431) with a 95% CI of 89.42% - 94.67%. This data supports rejection
of the null hypothesis (H
0
) that agreement was no greater than 75% with a p-value<0.0001.
The percentage Positive Agreement (sensitivity) or the ability of Bond Oracle HER2 IHC System
to correctly identify HercepTest positive cases (the percentage of specimens scored positive
by both Bond Oracle HER2 IHC System and HercepTest out of all the HercepTest positive
cases) was 84.87% (129/152) with a 95% CI of 78.17%-90.16%. The percentage Negative
Agreement (specificity) or the ability of the test to correctly identify HercepTest negative cases
(the percentage of specimens scored negative by both Bond Oracle HER2 IHC System and
HercepTest out of all the HercepTest negative cases) was 96.42% (269/279) with a 95% CI of
93.51%-98.27%.
HercepTest
Negative
Positive
Totals
Bond Oracle HER2
IHC System
Negative
269
23
292
Positive
10
129
139
Totals
279
152
431
2x2 Concordance (95% CI) = 92.34% (89.42 to 94.67%); p<0.0001
Table 6. 2x2 concordance of Bond Oracle HER2 IHC System with HercepTest
3x3 Concordance Results
Data was grouped as negative (0 or 1+), equivocal (2+) or positive (3+) for 3x3 analysis and
showed a concordance of 86.54% (373/431) with a 95% CI of 82.95% to 89.62 %. Therefore, the null
hypothesis (H
0
) that agreement was no greater than 75% was rejected with a p-value<0.0001.
The percentage Positive Agreement for 3+ (the percentage of specimens scored 3+ positive
by both Bond Oracle HER2 IHC System and HercepTest out of all the 3+ HercepTest positive
cases) in this study was 73.33% (66/90) with a 95% CI of 62.97% to 82.11%. The percentage
Negative Agreement was 96.42% (269/279) with a 95% CI of 93.51% to 98.27. See Table 7.
HercepTest
Negative
(0 or 1+)
2+
3+
Totals
Bond Oracle
HER2 IHC
System
Negative
(0 or 1+)
269
23
0
292
2+
10
38
24
72
3+
0
1
66
67
Totals
279
62
90
431
3x3 Concordance (95% CI) = 86.54% (82.95% to 89.62 %); p<0.0001
Table 7. 3x3 concordance of Bond Oracle HER2 IHC System with HercepTest