A test that is reliable is always valid.

A test that is reliable is always valid.

• A. Sometimes
• B. Never
• C. False
• D. True

Answer: (C)

Reliability and validity are related but different ideas about how well a test works. Reliability is about consistency—does the test give the same results if you retake it or if different people score it the same way? Validity is about accuracy—does the test actually measure what it’s intended to measure? A test can be reliable but not valid. For example, a scale might always show the same weight for a person, so it’s reliable, but if that weight isn’t the person’s true weight, it isn’t valid for measuring actual weight. In education, a quiz could yield very consistent scores but still not truly assess the intended skill or knowledge if the items don’t align with the target content. Because reliability only speaks to consistency and not about whether the content or construct is being measured correctly, it does not guarantee validity. A test must be valid to be useful for making decisions about what a student knows or can do, and validity typically relies on, but goes beyond, reliability.

Reliability and validity are related but different ideas about how well a test works. Reliability is about consistency—does the test give the same results if you retake it or if different people score it the same way? Validity is about accuracy—does the test actually measure what it’s intended to measure?

A test can be reliable but not valid. For example, a scale might always show the same weight for a person, so it’s reliable, but if that weight isn’t the person’s true weight, it isn’t valid for measuring actual weight. In education, a quiz could yield very consistent scores but still not truly assess the intended skill or knowledge if the items don’t align with the target content.

Because reliability only speaks to consistency and not about whether the content or construct is being measured correctly, it does not guarantee validity. A test must be valid to be useful for making decisions about what a student knows or can do, and validity typically relies on, but goes beyond, reliability.