ERP Micro December 2019

AOAC INTERNATIONAL Expert Review Panel Chair Report for Microbiology for Foods and Environmental Surfaces Page 4 of 5

MEETING MINUTES

I. Welcome and Introductions The Expert Review Panel Co-Chairs, Wendy McMahon and Michael Brodsky welcomed Expert Review Panel (ERP) members and initiated introductions. The Chair(s) discussed with the panel the goal of the meeting.

II. Joint Discussion between ERP Members and Committee on Statistics A. Fractional Recovery Discussion

Sydney Sudberg, Chair of the AOAC Committee on Statistics, presented an overview of the discussions regarding the proposed “Statistical Analysis of Interlaboratory Studies” by Robert LaBudde. The ERP had previously agreed to abide by the future recommendation of the AOAC Committee on Statistics for the required number of test replicates for the various fractional ranges. B. Update on Proposed Changes to Appendix J: AOAC INTERNATIONAL Methods Committee Guidelines for Validation of Microbiological Methods for Foods and Environmental Surfaces Paul Wehling of General Mills, Inc., presented an overview of the current changes to Annex A: MPN Analysis of Contaminated Matrix, Annex B: Raw Format Data Table Template and Example for Qualitative Method Single Laboratory and Collaborative Studies, Annex C: Calculation of POD and dPOD Values from Qualitative Method Single Laboratory Data, Annex D: Summary Data Table for Qualitative Method Single Laboratory Studies, Annex E: Example of Graph of POD Values from Qualitative Method Single Laboratory Data, Annex F: Calculation of LPOD and dLPOD Values from Qualitative Method Collaborative Study Data, and Annex G: Data Summary Table Template and an Example for Qualitative Method Collaborative Studies. Wehling also discussed and presented the proposed changes to the statistical tables for paired and unpaired studies. The ERP decided to propose a task group combined of ERP members, Committee on Statistics members, and other vested interested members. Proposed task group members (including select members of the AOAC Committee on Statistics): Tom Hammack, Erin Crowley, Wendy McMahon, Sharon Brunelle, Sara Murphy, Moran Wallace, and Drew Lienau. The scope of the task group is to clarify single laboratory and collaborative study validation information for fractional recovery of harmonized method and to propose a recommendation to the AOAC Expert Review Panel for Microbiology for Foods and Environmental Surfaces. A few suggestions as follows were discussed: 1) Recommended that a harmonized protocol would be acceptable. 2) A notation/disclaimer stating that the use of 8 replicates, themethod may risk failing an AOAC INTERNATIONAL validation. 3) Revision to Table 2 (Statistical Analysis of Interlaboratory Studies): 1) Clarify title 2) include a notation for ρ = aggregate mean of all the labs combined., and 3) Number of replicates in total 4) Examine and determine the impact of 31% - 69% with 8 replicates. III. ERP Technical Reviews and Processes Deborah McKenzie briefly discussed a possible review of structure with the AOAC Official Methods Board to better allocate the resources of our expert reviewers. IV. Announcements and Action Item AOAC Staff will assemble the proposed task force to address the concerns of the ERP in relation to fractional recovery ranges.

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