3.7.1 Assay Quality Metrics in HTS

The statistical robustness of an HTS assay is conventionally quantified using the Z-factor, a dimensionless parameter that incorporates both the separation...

The statistical robustness of an HTS assay is conventionally quantified using the Z-factor, a dimensionless parameter that incorporates both the separation between positive and negative control signals and the variability (standard deviation) of each. A Z-factor between 0.5 and 1.0 is generally regarded as indicating an excellent assay suitable for HTS deployment, while a Z-factor below 0.5 signals excessive variability or insufficient signal window, requiring assay optimisation before large-scale screening proceeds. Coefficient of variation (CV%) across replicate control wells and the signal-to-background ratio are further routinely monitored quality metrics.