Validity is defined as what in measurement?

• A. Standardization
• B. Reliability
• C. Measures the degree to which a variable measures what it is intended to measure
• D. Randomization quality

Answer: (C)

Validity is the extent to which a measurement actually measures what it is intended to measure. If a depression questionnaire truly reflects depressive symptoms and not other factors like anxiety or social desirability, it is valid. There are different kinds of validity, such as content validity (the items cover all aspects of the construct), criterion validity (scores relate well to a gold standard), and construct validity (the results fit theoretical expectations with related variables). It’s possible for a measure to be reliable—giving consistent results—yet not valid if it’s not actually measuring the intended concept. In contrast, standardization refers to uniform procedures for administration, and randomization quality pertains to study design, not measurement accuracy. So the definition aligns with measuring the degree to which the instrument captures what it’s meant to measure.