OMA Protocol Review: OMAMAN-56 Sulfites in Shrimp
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
=
is the i th value, Xbar is the mean value, and n is the number of values.
where X i
( 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
X
s
where
is the mean analytical value of the known negative matrix; is the intercept of the plot of s r
0
b
m
vs. mean value; and
is the slope of the plot.
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