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with the applicability statement.
ER 8
Yes
Supporting Data and information: Does data collected support the criteria given in the collaborative study protocol?
ER 1
Yes.
ER 2
Yes
ER 3
yes
ER 4
YES, the data has been generated in accordance to the collaborative study protocol.
ER 5
The data supports the criteria regarding the use of DF broth and one step enrichment protocol.
ER 6
yes
ER 7
Please remove the "For Other Matrices" sections from both Tables A and B, so that the Tables will be
aligned with the applicability statement (see above).
ER 8
Yes
Are there any concerns regarding the safety of the method?
ER 1
No
ER 2
No
ER 3
No
ER 4
No
ER 5
To be covered once Safety Advisor review is presented.
ER 6
No
ER 7
No.
ER 8
No
Are there any concerns regarding the data manipulation, data tables, or statistical analysis?
ER 1
No
ER 2
No
ER 3
No
ER 4
I would like to bring the following points for discussion by the group: • While the AOAC 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,
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. • It is interesting to see
that sample 9 in the low sample set 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
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