Microsoft Word - Candidates for 2017 ERP of the Year

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guidelines under Appendix J, Annex F prescribe the analysis of the data set as a whole for the POD analysis, is there a need to also consider the equivalency of the methods in each individual lab. This may be outside of the realm of the guidelines, but I believe that this type of evaluation could be useful. For example in this method for the cottage chese, overall the combined data set produced 66 and 64 positive results for the presumptive and confirmed candidate results respectively, while a total of 73 positives were detected using the reference method. As a whole in this case the LCL and the UCL of the dPOD encompasses the 0 value showing no statistical differences. This is however not true for two of the participating laboratories, laboratory 7 and 9 both produced differences between the candidate and the reference method which are statistically significant. In both cases the candidate method produced results that were much lower than the reference method. Does this indicate that there was a particular problem with these sample sets, the method or the analysis? The table below shows an example of the results in lab 7 where the candidate method detected 4 confirmed positives whereas the reference method detected 10.The deli turkey sample set does not appear to have the same issue above. • It is interesting to see that sample 9 in the low sample set for cottage cheese of the candidate method for labs 7-15 all produced negative results and overall only one lab that in the included sample set produced a positive sample. To illustrate this point, 1 out of 11 labs had a positive sample giving a POD of 9%. This is much lower than the overall POD of about 50% for the sample set and falls outside of the statistical (normal) distribution expected with a 50 % fractional positive result. All other sample sets exhibit a more normal distribution of fractional positive results as would be expected. The same pattern does not repeat anywhere in the reference method data set. • The APC counts for the sample sets seem to have a broad range of values where the range covers 3 logs for cottage cheese and 4 logs for the deli turkey of counts. I was not expecting such a difference given the method that is used to enumerate these results is a well validated and used quantitative method.

Some of the numbers need to be checked and edited accordingly.

ER 6 ER 7 ER 8

No

No General Comments (2) ER 1 None. ER 2

Suggestions are given below for shortening the manuscript

NA

ER 3 ER 4

No additional comments

ER 5 ER 6 ER 7 ER 8 EDITORIAL EVALUATION CRITERIA Is the Validation Study Manuscript in a format acceptable to AOAC? ER 1 Yes ER 2 Yes

03/12/2018