EQAS Program User Guide - QCNet

Chapter 9: GlossaryLate ResultA participant submitted result for a select sample that is received at Bio-Rad EQAS after that sample hasclosed (Sample Due Date). Late results are identified in EQAS reports by a symbol or as text. Lateresults are compared to the dataset that was in place at the time the sample was closed. They are notincluded in the dataset until a recalculation at the end of a cycle to include all late and amended results.Levey-Jennings ChartA commonly used trend chart in which individual deviation measurements are plotted around a linerepresenting zero deviation. Allowable limits of error (Z-score lines) are displayed in parallel to the zerodeviation line. These limits being defined deviations from the consensus mean, ± 1, 2 and 3 Z-score. Time isdisplayed on the X-axis (horizontal). The consensus mean for your comparator is noted on the top of theLevey-Jennings chart. This chart provides a visual representation of how well a laboratory test is working.LyophilizedThe characteristic describing the result of the process of vacuum-freeze-drying a liquid material to make itscomponents more stable.MatrixRefers to the physical and chemical nature of the specimen, the substances present and their concentration.For example: urine, serum, plasma, or whole blood.Method1 Method is a comparator encompassing users reporting on the same analyte using a specific methodology.This is generally the second level of comparison for your results. There is no differentiation betweeninstruments or reagents at this comparator. There must be at least 9 results present at the Methodcomparator level, or your comparison assessment moves to the next level (All Results). For multi-modaldata distributions, comparison at Your Method is provided for informational purposes only.2 Methodology.MethodologyThe means by which an analyte is measured.Missing ResultA laboratory result that was expected by Bio-Rad EQAS for a registered test but not received prior to theclose of a sample (Sample Due Date). A missing result is identified in your EQAS reports with the symboland a dash (-) in place of the missing value.ModeA comparator comprised of methods (can be more than one) or instrument and reagent (peer) combinationsthat together, produce a similar result that is significantly different than other results being reported for thesame analyte or parameter. The Mode is a subset of the “All Results” comparator. Modes are only createdwhen there is a multi-modal distribution of the results. This allows for a more specific estimation of alaboratory’s comparison versus the use of all reported results.100 EQAS Program User Guide