SPADA Draft Documents

Glossary

847

( a ) Accuracy.— Closeness of agreement between a quantity value obtained by measurement 848 and the true value of the measurand (from VIM 2007). This is essentially the rate of the assay 849 giving the correct result. Assays with high accuracy have low occurrence of both false positives 850 and false negatives. The equation for accuracy is given by: 851 where TP = true positives, TN = true negatives, FP = false positives, and FN = false negatives. 852 ( b ) PCR assay design .—An in silico process to identify the genomic region that contains the 853 assay components such as primers and probe. 854 ( c ) Assay development .—Refers to the entire process from target identification/ selection, 855 assay design, validation, optimization, matrix testing, preparation of the packages for DoD 856 acceptance, FDA EUA, 510k, etc 857 ( d ) Assay improvement .—Any improvement of existing assays in response to a variety of 858 outcomes from initial testing or field testing. E.g., signature erosion, failure of assays in certain 859 conditions or specific matrices, or in multiplex formats 860 ( e ) Assay optimization (IS) .— In silico optimization of parameters 861 ( f ) Assay optimization (Wet lab) .—Refers to wet lab testing of the designs from the in silico 862 process under different conditions of PCR (concentrations of components, temperature, etc). 863 ( g ) Assay performance .—An overall assessment of the sensitivity, specificity, and LoD of an 864 assay in a particular sample matrix. 865 ( h ) Assay stewardship (assay performance monitoring) .— In silico validation of assay 866 performance with the availability of new genomic sequences over time. 867 = + + + +

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