For more than a decade, the scientific literature has stressed the preeminence of pre-analytical error. Often these papers play a zero-sum game, emphasizing pre- and post-analytical quality while diminishing the importance of analytical quality. In this lesson, sources of errors for the pre-analytic and post-analytic phases of the Total Testing Process are discussed, along with possible solutions. Finally, the occurrence of these errors are rated on a Sigma-scale, to put pre-analytical problems into context with analytical performance. (Preview)

Historically, the first publication of the “Westgard Rules” was shown with an example from
clinical chemistry. As a result, some people believe that QC does not apply to other areas of testing, like hematology, immunology, etc. nor to the new technologies and devices that have been introduced to the laboratory in recent years. This lesson explains how QC techniques apply and can be implemented in "other" areas of testing. (Preview)