Normal and Abnormal Controls

A normal control product contains normal levels for the analyte. An abnormal control product contains the analyte at a concentration above or below the normal range for the analyte. For example, the normal range for a potassium level is approximately 3.5–5.0 mmol/L. A normal control contains potassium at a level within this range. An abnormal control contains potassium at a level below 3.5 mmol/L or above 5.0 mmol/L.