Quality control for reagent strips should be performed in which manner?

Quality control for reagent strips should be performed in which manner?

• A. Run positive controls daily and negative controls when opening a new bottle
• B. Run both positive and negative controls only when expiration date passes
• C. Run both positive and negative controls daily
• D. Run positive controls daily and negative controls weekly

Answer: (C)

Quality control for reagent strips should be done daily with both positive and negative controls to verify that the test system is functioning correctly each day. A positive control shows that the strip’s detection chemistry responds as expected when an analyte is present, confirming the ability to produce a true positive result. A negative control confirms there is no unwanted signal when analytes are absent or below the detection level, protecting against false positives. Doing both controls daily catches issues early—such as reagent degradation, lot-to-lot variation, or storage problems—so patient results remain reliable. Relying on only a positive control or delaying negative testing until a new bottle is opened allows problems to go unnoticed and can lead to inaccurate results. Expiration date checks or weekly negative controls do not provide the same immediate assurance of daily performance. Therefore, running both positive and negative controls daily is the best approach.

Quality control for reagent strips should be done daily with both positive and negative controls to verify that the test system is functioning correctly each day. A positive control shows that the strip’s detection chemistry responds as expected when an analyte is present, confirming the ability to produce a true positive result. A negative control confirms there is no unwanted signal when analytes are absent or below the detection level, protecting against false positives. Doing both controls daily catches issues early—such as reagent degradation, lot-to-lot variation, or storage problems—so patient results remain reliable. Relying on only a positive control or delaying negative testing until a new bottle is opened allows problems to go unnoticed and can lead to inaccurate results. Expiration date checks or weekly negative controls do not provide the same immediate assurance of daily performance. Therefore, running both positive and negative controls daily is the best approach.