Sensitivity |
Minimum amount or concentration of an analyte required to generate a reliable result (“analyte” is used here generically and may refer to an entire microorganism or to an ion) |
Specificity |
Ability to measure the intended target, analyte, or signature |
Reproducibility |
Closeness of agreement between the results of successive measurements of the same analyte under similar but not necessarily identical conditions |
Precision |
Degree to which individual measurements of the same sample are similar |
Accuracy |
Degree to which the measured material or analyte is similar to its true value |
Robustness |
Stability of analytical performance under variable conditions |
Reference samples |
Samples for testing the performance of the assay (e.g., reference panels of the target and mock or nonprobative materials) corresponding to the intended application of the assay. Assays should be evaluated for performance in the presence of potential interfering substances that may mimic some conditions encountered with forensic samples. |
Input values |
Range of quantities of an analyte that can be analyzed reliably |
Quantitation |
Amount or concentration of an analyte |
Dynamic range |
Range of values or limits within which precision is held |
Limit of detection |
Minimum level at which all replicates are consistently positive |
Controls |
Test materials of known value for the measured analyte (includes blind samples, negative controls, and positive controls) |
Selectivity |
Ability to measure and to differentiate the analyte in the presence of other materials that may be present |
Window of performance for operational steps of assay |
Parameters that define analytical condition variations that will not substantially affect performance or reliability |
Critical equipment calibration |
Equipment requiring calibration prior to its initial use and on a regular basis thereafter |
Critical reagents |
Reagents determined by empirical studies or routine practice to require testing on known samples prior to use with evidentiary materials in order to prevent an unnecessary consumption of forensic samples |
Databases |
Collection of data to be used to support an interpretation of results |
Personnel training, proficiency, and safety |
Qualifications and education of the personnel to conduct the analysis safely |
Interpretation criteria for results |
Analysis (statistical or qualitative) used and confidence level of a match or result |