Which term describes instruments that measure are accurate and operate correctly?

Which term describes instruments that measure are accurate and operate correctly?

• A. Validity
• B. Specificity
• C. Accuracy
• D. Reliability

Answer: (C)

Accuracy is about how close a measurement is to the true value. When an instrument is accurate, its readings reflect the real value and are free from systematic bias, meaning it measures correctly. Reliability, by contrast, is about consistency across repeated measurements—an instrument can be reliable (always reads the same) but not accurate if that consistent value is off from the true value. Validity concerns whether the instrument measures what it’s supposed to measure, not necessarily how close the readings are to the actual value. Specificity isn’t the relevant idea in this general measurement context.

Accuracy is about how close a measurement is to the true value. When an instrument is accurate, its readings reflect the real value and are free from systematic bias, meaning it measures correctly. Reliability, by contrast, is about consistency across repeated measurements—an instrument can be reliable (always reads the same) but not accurate if that consistent value is off from the true value. Validity concerns whether the instrument measures what it’s supposed to measure, not necessarily how close the readings are to the actual value. Specificity isn’t the relevant idea in this general measurement context.