146-147 / 1195
1
Table 9. BAX® System vs. Reference Method Results – Produce
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
Peas (25 g)
LB
Control
5
0
0
(0, 0.43)
0
0
(0, 0.43)
0
(-0.45, 0.45)
0.43 (0.23, 0.72)
20
7
0.35
(0.18, 0.57)
7
0.35
(0.18, 0.57)
0
(-0.14, 0.14)
1.8 (1.0, 3.0)
5
4
0.80
(0.38, 1.0)
4
0.80
(0.38, 1.0)
0
(-0.45, 0.45)
Peas (25 g)
MP media
Control
5
0
0
(0, 0.43)
0
0
(0, 0.43)
0
(-0.43, 0.43)
0.43 (0.23, 0.72)
20
8
0.40
(0.22, 0.61)
7
0.35
(0.18, 0.57)
0.05
(-0.23, 0.32)
1.8 (1.0, 3.0)
5
5
1.0
(0.57, 1.0)
4
0.80
(0.38, 1.0)
0.20
(-0.27, 0.62)
Orange juice
(25 mL)
UPB / BHI
Control
5
0
0
(0, 0.43)
0
0
(0, 0.43)
0
(-0.45, 0.45)
0.17 (0.051, 0.34)
20
3
0.15
(0.050, 0.36)
3
0.15
(0.050, 0.36)
0
(-0.14, 0.14)
Orange juice
(25 mL)
MP media
/ BHI
Control
5
0
0
(0, 0.43)
0
0
(0, 0.43)
0
(-0.43, 0.43)
0.17 (0.051, 0.34)
20
7
0.35
(0.18, 0.57)
3
0.15
(0.050, 0.36)
0.20
(-0.070, 0.44)
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
Dupont BAX Salmonella Pre- Collaborative Study
For Expert Review Panel Use Only
Do Not Distribute
AOAC INTERNATIONAL