Which statement about reliability and validity is true?

• A. A test can be reliable without being valid
• B. Validity guarantees reliability
• C. A test must be both reliable and valid to be useful
• D. Reliability and validity are the same

Answer: (A)

Reliability is about consistency — a test should give the same result under the same conditions. Validity is about accuracy — the test should actually measure what it’s supposed to measure. These are related but distinct ideas.

A test can be reliable without being valid. The key is that you can get repeatable, consistent results even if those results don’t reflect the true construct you want to assess. For example, a scale could consistently read the same weight every time, but if that weight isn’t the person’s true weight (it’s off by a constant amount), the measurement is reliable but not valid. Validity would require adjusting or calibrating the scale so that its readings match the true weight, which may then also involve checking that it truly measures weight rather than something else.

The other statements blur this separation. Validity does not automatically guarantee reliability, since a measure can be valid in what it intends to assess but still yield inconsistent results across trials or items. And while in practice we want both reliable and valid, the fundamental point is that reliability and validity are not the same thing, and reliability does not imply validity.