Accreditation and Quality Assurance

, Volume 12, Issue 1, pp 54–54

Evaluation of the limit of performance of an analytical method based on a statistical calculation of its critical concentrations according to iso standard 11843: Application to routine control of banned veterinary drug residues in food according to European Decision 657/2002/EC

Erratum

Accred Qual Assur (2006) 11(1–2):58–62

The hereabove mentionned article published in the April 2006 Issue No 1–2 Page 58–62 of the Journal contains a parenthesis mistake in 2 formulas of its page 59. This mistake may lead to corruption in the calculations for the readers not familiar with ISO Standard 11843–2. In the part entitled Concept of calculation of critical concentrations according to Standard ISO11843, for the calculation of CCα and CCβ applied to what is called MRL substances,

it is recommended to use the following formulas where is added a set of parenthesis at the numerator of the 3rd term under the square root :
$${\it CC}\alpha = x_{\it MRL} + t_{(\alpha ,{\it IJ} - 2)} .\frac{{\hat \sigma }}{{\hat b}}.\sqrt {\frac{1}{K} + \frac{1}{{\it \it I.J}} + \frac{{(x_{\it MRL} - \bar x)^2}}{{\sum {(x_{ij} - \bar x} )^2}}}$$
$${\it CC}\beta = x_{\it MRL} + \delta _{({\it I.J} - 2;\alpha ;\beta )} .\frac{{\hat \sigma }}{{\hat b}}.\sqrt {\frac{1}{K} + \frac{1}{{\it I.J}} + \frac{{(x_{\it MRL} - \bar x)^2}}{{\sum {(x_{ij} - \bar x} )^2}}}$$