Microbiology Methods for ERP Review 3-2020

68

GENE ‐ UP ® SLM 2 Collaborative Study

July 2019

(1) Determine POD values for each matrix and concentration  ‐  the number of positive outcomes divided by the total number of trials. (2) Estimate of repeatability  ‐  standard deviation (s r ) and confidence intervals. (3) Estimate of reproducibility – standard deviation of the laboratory POD values (s R ) and confidence intervals. (4) Estimate among laboratory repeatability (s L ) and confidence intervals (5) Cross laboratory probability of detection (LPOD) – LPODs by matrix and concentration with 95% confidence intervals for candidate method (presumptive and confirmed) and reference method results. (6) Difference of cross ‐ laboratory probability of detection (dLPOD) – difference probability of detection is the difference between any two LPOD values. (a) Estimate dLPOD C as the difference between the candidate and reference LPOD values, include CIs. (b) Estimate dLPOD CP as the difference between the presumptive and confirmed LPOD values, include CIs. (c) If the CI of a dLPOD does not contain zero, then the difference is statistically significant. (7) For each matrix, graph LPOD, and dLPOD values by level with 95% confidence intervals.

8) Appendices a) 8.1 – Instructions to Collaborators b) 8.2 – Test Portion Data Report Forms c) 8.3 – Study Materials d) 8.4 – Flow Diagram – Raw Ground Beef (375 g) e) 8.5 – Collaborator Comment Form f) 8.6 – User Manual

13