AOAC ISPAM Stakeholder Panel Meeting Book 3-13-18

Quantitative Microbiology Validation Acceptance Criteria

ƒ Appendix J: AOAC INTERNATIONAL Method Committee Guidelines for Validation of Microbiological Methods for Food and Environmental Surfaces ƒ Adopted in 2011 and implemented in 2012 ƒ Heavy emphasis on design and statistical change to Qualitative Microbiology Evaluations ƒ Design of Quantitative Microbiology validations (from previous guidelines) did not change

• 3-4 levels of contamination with 5 replicate samples at each level • The statistical analysis component was significantly changed.

Quantitative Microbiology Validation Acceptance Criteria

ƒ Original Statistics - ƒ Log 10 transform data • Can’t be performed for Uninoculated Control Level (0 Data Points) ƒ Perform ANOVA or t-test to determine if mean replicates at each level are different ƒ Calculate repeatability by determining the standard deviation (s r ) at each level ƒ Graph the mean results for each contamination level (Candidate – Y axis, reference – X axis) and determine the slope and linear correlation coefficient (r 2 ) ƒ Acceptance Criteria per matrix per level was established • p value (obtained from ANOVA or t-test) should be >0.05 to establish equivalence between methods • It still left many unresolved questions on data interpretation