ERP Micro December 2019

Table B: Assurance ® GDS for E . coli O157:H7 Tq, Candidate vs. Reference – POD Results: Manual Sample Processing

MPN a / Test Portion or CFU b /Cloth

Candidate

Reference

Test Portion Size

Matrix

N c

dPOD C g

95% CI h

x d POD C e

95% CI

X

POD R f

95% CI

5

0

0.00 0.45 1.00 0.00 0.50 0.60 0.00 0.25 0.80

0.00, 0.43 0 0.26, 0.66 0 0.57, 1.00 2

0.00 0.00 0.40 0.00 0.10 0.20 0.00 0.20 0.80

0.00, 0.43 0.16, 0.61 0.18, 0.77 0.00, 0.43 0.03, 0.30 0.03, 0.64 0.00, 0.43 0.08, 0.42 0.38, 0.96

0.00 0.45 0.60 0.00 0.40 0.40 0.00 0.05 0.00

-0.43, 0.43 0.20, 0.66 0.03, 0.88 -0.43, 0.43 0.12, 0.61 -0.16, 0.75 -0.43, 0.43 -0.21, 0.30 -0.45, 0.45

-

a MPN = Most

Frozen finely textured beef

20 9

375 g

0.00 (0.00, 0.09)

5 5

5 0

0.46 (0.20, 1.02)

0.00, 0.43 0.30, 0.70 0.23, 0.88

0 2 1

N/A i

Carcass cloth j

20 10

1 cloth

0.80

5 5

3 0

3.00

0.00, 0.43 0 0.11, 0.47 4 0.38, 0.96 4

-

Green onions

0.17 (0.03, 0.033) 20 5

25 g

5

4

2.00 (0.96, 4.13)

Probable Number is calculated using the LCF MPN calculator provided by AOAC RI, with 95% confidence interval. b CFU/cloth = Results of the CFU/test area were determined by plating the inoculum for each matrix in triplicate. c N = Number of test portions. d x = Number of positive test portions. e POD C = Candidate method confirmed positive outcomes divided by the total number of trials. f POD R = Reference method confirmed positive outcomes divided by the total number of trials. g dPOD C = Difference between the confirmed candidate method result and reference method confirmed result POD values. h 95% CI = If the confidence interval of a dPOD does not contain zero, then the difference is statistically significant at the 5% level. I N/A = Not applicable. j MPN not available for carcass cloth. Low and high inoculation levels CFU/cloth indicated. Table C: Assurance ® GDS for E . coli O157:H7 Tq, Presumptive vs. Traditional Confirmed – POD Result: Manual Sample Processing