Page 341 - Analytical method for food addtives

228 Analytical methods for food additives

Table 25.3 Performance characteristics for aluminium in milk powder 1
Sample Milk powder
Analyte Aluminium
No. of laboratories 16
Units mg/kg
Mean value 15.87
S 0.83
r
RSD 5.2 %
r
r 2.33
S 2.90
R
RSD 18.3 %
R
R 8.21
Key
Mean The observed mean. The mean obtained from the collaborative trial data.
r Repeatability (within laboratory variation). The value below which the absolute difference
between two single test results obtained with the same method on identical test material under
the same conditions may be expected to lie with 95 % probability.
S The standard deviation of the repeatability.
r
RSD The relative standard deviation of the repeatability (S × 100/mean).
r r
R Reproducibility (between-lab variation). The value below which the absolute difference
between two single test results obtained with the same method on the identical test material
under different conditions may be expected to lie with 95 % probability.
S The standard deviation of the reproducibility.
R
RSD The relative standard deviation of the reproducibility (S × 100/mean).
R R