Assay data quality assessment.

An overview of the characteristics of classical and outlier-resistant data summaries is provided. The latter are important because outlier data can skew results and decisions based on them. The simple data summaries are the basis for all composite assay and screening data quality measures, for example, the signal-to-noise ratio, signal-to-background ratio, assay and screening window coefficients Z ' and Z, or strictly standardized mean difference (SSMD). In addition to the measures of assay reliability which are based on assessing the size of the "signal windows," some measures for the characterization of the degree of agreement of repeated measurements are also outlined.