The measure of how well a system reproduces an established output under uniform conditions is ______.

• A. Repeatability
• B. Reproducibility
• C. Accuracy
• D. Precision

Answer: (A)

Repeatability measures how tightly repeated measurements match the established output when everything is kept the same—same instrument, same setup, same operator, and the same environment. When you test a known reference value under uniform conditions, the degree to which the results cluster around that reference shows how repeatable the system is. A small spread indicates high repeatability, meaning the system can reproduce the output reliably under those fixed conditions. Reproducibility would come into play if conditions varied (different operators, instruments, locations), which isn’t the scenario here. Accuracy concerns how close measurements are to the true value, not how consistently they reproduce the same result. Precision relates to how close the measurements are to each other in general, but the specific term for fixed-condition consistency is repeatability.