Where Are the Preanalytical Stability Standards

Minimizing systematic and random errors within the testing process enables the reporting of quality results. Laboratories have developed multiple strategies to control the variables within the analytical testing phase, but often have little authority over the variables imposed during the pre- and postanalytical phases. Unlike the postanalytical processes, which mainly rely on correct result transmission and subsequent interpretation, preanalytical processes can directly influence the analytical value reported by the laboratory (1). This is a conundrum that requires laboratory employees to define acceptability criteria for parameters such as proper mixing of samples with any required collection tube additives such as heparin or EDTA, the number of hours the sample can remain unprocessed (for serum/plasma tests), transport temperature, and the number of days following collection that additional testing can be added on, which is often storage temperature-dependent. All these parameters (and more!) can be generally classified under “stability.” During the assay development process, …