What is the minimum requirement for QC of a total protein assay within a 24-hour period?

For quality control (QC) in clinical laboratory testing, especially for assays like total protein, the requirements ensure the reliability and accuracy of results over time. The minimum requirement of assaying two levels within 24 hours is a standard practice designed to account for variability in assay performance throughout the day.

By assaying two different control levels (typically a low and a high control) within that timeframe, laboratories can monitor the assay's performance, detect any drift in results, and ensure that the assay is working within established limits. This approach provides an adequate check of the assay's precision and quality without being overly burdensome in terms of time and resources.

In contrast, more frequent testing or an increased number of control levels could provide additional assurance of assay reliability, but for a minimum requirement, two levels within a 24-hour period is sufficient to maintain quality and ensure that patient results are accurate and reliable. This balance between adequate QC and practical laboratory workflow is key to maintaining high standards in clinical chemistry.