This implementation guide describes the minimum procedures necessary for a medical laboratory to verify that new reagent lots, when received and implemented by the laboratory, will produce results consistent with previous reagent lots. Reagent lot performance is validated by the developer before release and distribution; however, the laboratory needs to verify each new reagent lot it receives. Changes in performance with a new reagent lot could be due to:
• Changes in reagent component materials
• Instability of a component in a reagent
• Reagents that were compromised in transportation or storage
• Incorrect calibration of the new reagent lot

Verifying that these potential changes have not occurred is important to ensure the quality of laboratory results. For additional information on the acceptability of a reagent lot change, see CLSI document EP26.1