Treatment of an observed bias


bias img 240x194Bias is routinely determined during the validation of analytical methods. Usually, the observed bias is not exactly zero. It is then important to decide whether the observed bias can reasonably be treated as unimportant, or whether some further action needs to be taken. This can be particularly difficult to decide when applying the principles of the 'Guide to the Expression of Uncertainty in measurement', which assumes that a correction has been applied for any important bias. 

This information leaflet has been prepared by the Eurachem Measurement Uncertainty and Tracability Working Group (see here for details). The leaflet discusses whether or not an observed significant bias should be corrected and the impact this may have on the measurement uncertainty (MU). The leaflet does not describe how to apply a correction or how to increase the uncertainty to take account of an uncorrected bias, though it does provide relevant literature sources.



 * 2nd printing; editorial amendment only


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Publication date

This leaflet was first published in English on 2017-05-27.

* The English copy on this page is a minor (editorial) amendment, published 2022-10-21; the recommendations are unchanged.