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Table 15. BAX® System vs. Reference Method Results – Miscellaneous
Sample Type
Media
MPN
a
Test
Portions
BAX® Method
Reference Method
dPOD
C
e
95% CI
f
X
b
POD
C
c
95% CI
f
X
b
POD
CC
d
95% CI
f
Peanut butter (25 g)
LB / BHI
Control
5
0
0
(0, 0.43)
0
0
(0, 0.43)
0
(-0.45, 0.45)
0.50 (0.26, 0.88)
20
9
0.45
(0.26, 0.66) 9
0.45
(0.26, 0.66)
0
(-0.14, 0.14)
5.0 (2.7, 8.9)
5
3
0.60
(0.23, 0.88) 3
0.60
(0.23, 0.88)
0
(-0.14, 0.14)
Peanut butter (25 g)
BPW / BHI
Control
5
0
0
(0, 0.43)
0
0
(0, 0.43)
0
(-0.45, 0.45)
0.50 (0.26, 0.88)
20
10
0.50
(0.30, 0.70) 9
0.45
(0.26, 0.66)
0.050
(-0.28, 0.33)
5.0 (2.7, 8.9)
5
5
1.0
(0.57, 1.0)
3
0.60
(0.23, 0.88)
0.40
(-0.11, 0.77)
Cocoa (25 g)
Nonfat Dry
Milk
Control
5
0
0
(0, 0.43)
0
0
(0, 0.43)
0
(-0.45, 0.45)
1.4 (0.96, 2.4)
20
13
0.65
(0.43, 0.82) 13
0.65
(0.43, 0.82)
0
(-0.14, 0.14)
12 (7.0, 19)
5
5
1.0
(0.57, 1.0)
5
1.0
(0.57, 1.0)
0
(-0.45, 0.45)
White pepper (25 g)
TSB
Control
5
0
0
(0, 0.43)
0
0
(0, 0.43)
0
(-0.45, 0.45)
1.3 (0.80, 2.2)
20
14
0.70
(0.48, 0.85) 14
0.70
(0.48, 0.85)
0
(-0.14, 0.14)
8.3 (4.8, 14)
5
5
1.0
(0.57, 1.0)
5
1.0
(0.57, 1.0)
0
(-0.45, 0.45)
Infant formula (25 g)
LB
Control
5
0
0
(0, 0.43)
0
0
(0, 0.43)
0
(-0.45, 0.45)
1.8 (1.1, 3.4)
20
16
0.80
(0.58, 0.92) 16
0.80
(0.58, 0.92)
0
(-0.25, 0.25)
2.0 (1.2, 3.7)
5
5
1.0
(0.57, 1.0)
5
1.0
(0.57, 1.0)
0
(-0.45, 0.45)
a
MPN = Most Probable Number based on the POD of reference method test portions using the AOAC MPN calculator (with 95% confidence interval)
2
b
X = Number of positive test portions
3
c
POD
C
=
Confirmed candidate method positive outcomes divided by the total number of trials
4
d
POD
R
= Confirmed reference method positive outcomes divided by the total number of trials
5
e
dPOD
C
= Difference between the candidate method and reference method POD values
6
f
95% CI = If the confidence interval of a dPOD does not contain zero, then the difference is statistically significant at the 5% level
7
8
9
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