ERP Sulfite Methods-Meeting Materials_4-2020

ERP for Sulfites in Seafood Methods Materials

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Intended users

‐ Food laboratories, for regulatory use.

‐ Technical staff of fish and aquaculture companies, including primary and processing sector.

Definitions ( a )

Linearity .—Linearity of the method extending beyond the set of standards or calibrators

supplied with the kit. The ability of the method to obtain test results proportional to the concentration.

( b ) Recovery .—Recovery is the ratio of the mean candidate method result to the true value,

expressed as a percentage, [mean cand /known spike] x 100 or [mean ref /known spike] x 100.

( d ) Accuracy .—Accuracy is the ratio of the mean candidate method result to the reference

method result, expressed as a percentage, [mean cand / mean ref ] x 100.

( e ) Bias .—Bias is the difference between the candidate method mean result and the true value, mean cand – known spike. ( f ) Standard Deviation of Repeatability .—s r = n



2

(

)

1 X X n   i

1

i



where X i is the i th value, Xbar is the mean value, and n is the number of values.

( g ) Relative Standard Deviation of Repeatability .—RSD r = [s r /mean cand ] x 100 ( h ) Relative Standard Deviation of Intermediate Reproducibility .—RSD i = [s i /mean cand ] x 100

Where mean mean cand is the mean value and s i the standard deviation obtained from two different

day/analyst/device data sets.

( i )

Limit of Detection (LOD) .—Mean + 2s r , or

  b s m

0 3.3 1 1.65  

X

0 X

b s

where

is the mean analytical value of the known negative matrix;

is the intercept of the plot of s r

m

vs. mean value; and

is the slope of the plot.

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04/16/2020