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Table 6. BAX® System Presumptive vs. Confirmed Results – Poultry and Egg

95% CI f

dPOD CP e

BAX® Presumptive

BAX® Confirmed

Test Portions

MPN a

Sample Type

Media

X b POD CP c

95% CI f

X b POD CC d

95% CI f

Control

5

0 8 5 5 0

0

0

5

0

(0-0.43)

0 0 0 0 0 0 0 0 0 0 0 0

(-0.45, 0.45) (-0.14, 0.14) (-0.45, 0.45) (-0.14, 0.14) (-0.45, 0.45) (-0.14, 0.14) (-0.45, 0.45) (-0.45, 0.45) (-0.14, 0.14) (-0.45, 0.45) (-0.45, 0.45)

Ground turkey (25 g)

BPW

0.63 (0.40, 1.0)

20

0.40

(0.22, 0.61) 8

0.40

(0.22, 0.61) (0.57, 1.0) (0.11, 0.47)

3.7 (2.0, 9.6)

5

1.0

(0.57, 1.0)

5

1.0

Chicken wings (25 g)

BPW

n/a

20

0.25

(0.11, 0.47) 5

0.25

Control

5

0

(0, 0.43)

0

0

(0, 0.43)

Dried eggs (25 g)

LB

1.5 (0.89, 2.5) 3.0 (2.0, 4.9)

20

15

0.75

(0.53, 0.89) 15

0.75

(0.53, 0.89) (0.57, 1.0)

5 5

5 0

1.0

(0.57, 1.0)

5 0

1.0

Control

0

(0, 0.43)

0

(0, 0.43)

Dried eggs (25 g)

BPW

1.5 (0.89, 2.5) 3.0 (2.0, 4.9)

20

16

0.80

(0.58, 0.92) 16

0.80

(0.58, 0.92) (0.57, 1.0)

5 5

5 0

1.0

(0.57, 1.0)

5 0

1.0

Control

0

(0, 0.43)

0

(0, 0.43)

Shell eggs (1,000 mL) MP media

1.6 (0.93, 3.1) (-0.14, 0.14) a MPN = Most Probable Number based on the POD of reference method test portions using the AOAC MPN calculator (with 95% confidence interval) 20 17 0.85 (0.64, 0.95) 17 0.85 (0.64, 0.95)

2 3 4 5 6 7 8 9

b X = Number of positive test portions

c POD CP = Candidate method presumptive positive outcomes divided by the total number of trials d POD CC = Candidate method confirmed positive outcomes divided by the total number of trials

e dPOD CP = Difference between the candidate method presumptive result and candidate method confirmed result POD values f 95% CI = If the confidence interval of a dPOD does not contain zero, then the difference is statistically significant at the 5% level

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