In routine analysis, QC samples are analyzed alongside the study samples to ensure that the analytical method remains within acceptable performance criteria. Typically, a set of QC samples is included in each analytical run. The results from these QC samples are then compared to predetermined acceptance criteria, such as accuracy (percentage deviation from nominal concentration) and precision (coefficient of variation). If the QC sample results fall within the acceptable range, the analytical run is considered valid. If not, the run may need to be repeated, and any issues identified and resolved.
