An Initial Demonstration of Capability must be conducted before using any method and under which conditions?

• A. Before using any method
• B. Only after a change in instrument
• C. Every two years
• D. Only after a failed QC

Answer: (A)

The main idea is proving the method can produce reliable results before you start using it. An Initial Demonstration of Capability is done to confirm that, with the current instrument setup, reagents, and personnel, the method meets predefined accuracy and precision requirements. This establishes a baseline performance so routine testing can be trusted. If something changes—such as swapping to a different instrument or a new batch of reagents—a re-demonstration is needed to show the method still performs acceptably. If QC results fail, you don’t perform the initial demonstration again; instead you investigate and correct the issue before continuing. There isn’t a standing rule to repeat this every two years; ongoing QC and method validation maintain confidence in performance.