Quant. MAC Working Group Meeting Book (March 13, 2019)

Proposed Technical Bulletin • If a low level of contamination for an alternative method has >2 data points with values of 0, the matrix will need to be re-evaluated • The following table provides guidance on evaluating statistically different bias with a method at a single level (low, medium, high):

Acceptable number of levels with statistically different bias at a single contamination level

Number of Matrices Evaluated

1-3 4-6

1 3 5

7-10 >10

NMT 8

Thank you

pat.m.bird@gmail.com pbird@aoac.org AOAC Research Institute Technical Consultant