SPADA Meeting Book

( aa ) Probability of detection (POD) .—The proportion of positive analytical outcomes for a

933 qualitative method for a given matrix at a given agent level or concentration. POD is 934 concentration dependent. 935

( bb ) Recommendation.— A suggestion or proposal as to the best course of action, especially

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one put forward by an authoritative body, that is beneficial to follow.

( cc ) Reference material (RM) .—Material that is sufficiently homogeneous and stable with 938 reference to specified properties, which has been established to be fit for its intended use in 939 measurement or in examination of nominal properties [from VIM 2012 (46)]. For purposes of 940 assay development, reference materials are templates used in development, testing, validation, 941 test and evaluation of the assay; e.g., live organisms, inactivated organisms, genomic materials 942 (DNA or RNA), synthetic plasmids, or even synthetic amplicons. 943 ( dd ) Robustness .—A study that tests the capacity of a method to remain unaffected by small 944 but deliberate variations in method parameters and which provides an indication of its reliability 945 during normal usage (from USP 31). 946 ( ee ) Sample (Material) .—The batch of matrix from which replicate test portions are removed 947 for analysis. The sample (uncontaminated or contaminated) contains agent at one specified level. 948 ( ff ) Sensitivity .—The true positive rate, which is the fraction of actual positive samples that 949 the assay returns a positive result. This is also called the “probability of detection.” Assays with 950 high sensitivity have a low occurrence of false negatives. Sensitivity should not be confused with 951 the limit of detection. The equation for sensitivity is given by: 952 954 primer and/or probe) that experimentally detects (e.g., by PCR or probe-based methods) most or 955 ൌ ൅ where TP = true positives and FN = false negatives. 953 ( gg ) Signature .—One or more oligonucleotide sequences (i.e. forward primer and/or reverse

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