The accuracy of an analytical procedure expresses the closeness of agreement between the value which is accepted either as a conventional true value or an accepted reference value and the value found. This is sometimes termed trueness. Accuracy should be established across the specified range of the analytical procedure.
Accuracy may also be demonstrated by the method of standard additions, or by cross-correlation of results with a second, independent, procedure. Accuracy may be inferred once precision, linearity and specificity have been established.