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You probably have not put as much thought into the clinical importance of independent, 3rd party quality control as Dr. Sonntag which is why we would like to share this article with you. As pointed out by Dr. Sonntag, ISO15189 states that, “The use of an independent third-party quality control should be considered either in

CLSI teaches us that it is important to know the difference between a “true” quantity of a substance and an individual measurement result. In other words, we need to know both the limit of the blank (LoB) and the limit of detection (LoD) [CLSI. Protocols for Determination of Limits of Detection and Limits of Quantitation;

Reports of biotin interference with laboratory tests are alarming. Biotin binds to streptavidin with high affinity, making the biotin-streptavidin system useful for immunoassays; however, elevated concentrations of biotin can interfere.  In competitive assays, useful for small molecules such as thyroxine (T4), there is an inverse association between analyte concentration and assay signal; biotin interference causes

  You have likely read method performance information with an arbitrary acceptance criterion e.g. plus or minus 10%. This is unfortunate because different measurands differ in the magnitude of error that impacts clinical decision making. Troponin, for example, needs to be measured more accurately and precisely than, let’s say, lactate dehydrogenase (LDH). Westgard and colleagues

The Clinical and Laboratory Standards Institute (CLSI) has made valuable recommendations for interference testing in document EP07. We created Excel spreadsheets, designed specifically to follow CLSI recommendations and to help simplify the process.  The cells highlighted in yellow are cells that require the input of information and data. The remaining cells are calculations embedded in

Clinical Laboratory Standards Institute (CLSI) provides important guidance for interference testing.1 Many laboratorians find the CLSI document difficult to follow, which is why we have developed simple instructions and Excel Interference Worksheets to make the interference testing experiment simpler and easier to interpret. CLSI recommends a screening experiment (paired difference testing) to identify assay interference,