This lesson discusses the math involved with QC practice. Despite the age of computers, we still have to crunch the numbers ourselves sometimes. Dr. Westgard discusses the terms Mean, SD, CV, Control Limits, z-scores and SDI's, explaining what they are, giving the equations, and demonstrating how to calculate them.
Basic QC Practices
Elsa F. Quam, BS, MT(ASCP) is one of our most popular guest essayists. Elsa rightly points out that while we concentrate on the statistics of quality control, we can't forget the selection of the control materials. Important attributes such as the stability, vial to vial variability, assayed versus unassayed, appropriate analyte levels, and pretreatment procedures affect the very success of the control procedure.