Question

Four different methods are described for validating the results of a particular analysis. Indicate for each whether the method primarily checks the accuracy of the analysis or the precision of the analysis.
(A) Five aliquots of the same sample are injected for gas chromatographic analysis by one person on the same day
(B) A known amount of analyte is added to an aliquot of the sample and analyzed with sample
(C) Aliquots from a blood sample are sent to three separate laboratories for analysis using the same method.
(D) Identical standard are analyzed by two different methods.

Answer 1

Answer:

A) Precision

B) Accuracy

C) Precision

D) Accuracy

Explanation:

Accuracy and Precision are factors that determine whether a given analysis is appropiate or not.

Accuracy refers to how close the experimental result is to a known, theoretical or accepted value. For this reason every method that checks the accuracy uses a standard -this could mean repeating the test using the standard instead of the sample, or adding a known amount of analyte to the sample-, in order to compare the results.

Precision refers to how close repeated the results of different tests are to each other, in other words, it refers to the repeatability of the method. A test for precision would require that the method is done several times, in order to check how close the results are to each other, regardless of whether those results are close to the expected value.