Objective analytical goals for interference in clinical biochemical methods have not yet been advocated. We propose that, since total analytical error is ideally less than half the within-subject biological coefficient of variation (CV1), the maximum allowable systematic error produced by an interferent (I) is:
where CVA is the relevant experimental analytical imprecision and SE is the systematic error. Such a goal may be applicable also to non-specificity, matrix effects and carryover.
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