Which statement accurately reflects a psychometric property important for a screening instrument?

Which statement accurately reflects a psychometric property important for a screening instrument?

• A. Reliability alone suffices for usefulness.
• B. Validity alone suffices for usefulness.
• C. Reliability and validity are both essential.
• D. Norms are the only essential property.

Answer: (C)

A screening instrument must be both reliable and valid. Reliability means the tool yields consistent results across time, scorers, or items, so you can trust that repeated administrations produce similar outcomes. Validity means the instrument actually measures the construct it intends to measure and corresponds with real-world criteria, so the results meaningfully reflect who is at risk. If you only have reliability, results can be consistent but meaningless if the tool isn’t measuring the right thing. If you only have validity, results might accurately target the construct but be too inconsistent to depend on across occasions. Norms help with interpretation but don’t by themselves ensure the tool is measuring the right thing or doing so consistently. Therefore, reliability and validity together are essential for a useful screening instrument.

A screening instrument must be both reliable and valid. Reliability means the tool yields consistent results across time, scorers, or items, so you can trust that repeated administrations produce similar outcomes. Validity means the instrument actually measures the construct it intends to measure and corresponds with real-world criteria, so the results meaningfully reflect who is at risk. If you only have reliability, results can be consistent but meaningless if the tool isn’t measuring the right thing. If you only have validity, results might accurately target the construct but be too inconsistent to depend on across occasions. Norms help with interpretation but don’t by themselves ensure the tool is measuring the right thing or doing so consistently. Therefore, reliability and validity together are essential for a useful screening instrument.