Which statement about a Gage R&R study is NOT typically correct?

Which statement about a Gage R&R study is NOT typically correct?

• A. Gage repeatability
• B. Gage reproducibility
• C. Part-to-part variation
• D. Calibration drift

Answer: (C)

Gage R&R focuses on how much variation in measurements comes from the measurement system itself, not from the parts. It breaks that variation into repeatability (the same operator using the same gauge measuring the same part yields the same result) and reproducibility (different operators or setups produce similar results). The parts’ own differences—part-to-part variation—are the inherent variability of the parts, not a property of the measurement system, so they aren’t treated as part of the Gage R&R calculation. Calibration drift is a factor that can degrade the stability of the measurement system over time and is something you monitor to keep measurements reliable, but it’s not the basic components of Gage R&R itself. Because Part-to-part variation lies outside the measurement system’s own variation, it isn’t typically described as part of a Gage R&R study, which is why that statement is the best choice.

Gage R&R focuses on how much variation in measurements comes from the measurement system itself, not from the parts. It breaks that variation into repeatability (the same operator using the same gauge measuring the same part yields the same result) and reproducibility (different operators or setups produce similar results). The parts’ own differences—part-to-part variation—are the inherent variability of the parts, not a property of the measurement system, so they aren’t treated as part of the Gage R&R calculation. Calibration drift is a factor that can degrade the stability of the measurement system over time and is something you monitor to keep measurements reliable, but it’s not the basic components of Gage R&R itself. Because Part-to-part variation lies outside the measurement system’s own variation, it isn’t typically described as part of a Gage R&R study, which is why that statement is the best choice.