Standard QC uses how many levels and how often?

• A. 2 levels every 24 hours
• B. 2 levels every 8 hours
• C. 3 levels every 24 hours
• D. 2 levels every 12 hours

Answer: (A)

Quality control in clinical chemistry relies on using two control levels to monitor assay performance across the measuring range. Having Level 1 and Level 2 helps detect both systematic bias and random variation, giving a more reliable check than a single level. Running these controls once each day (every 24 hours) verifies that the analyzer is operating within acceptable limits before patient results for that day are reported. While some settings may increase frequency or add more levels for specific tests or risk, the standard baseline is two control levels checked daily.