<P> Construct validity is "the degree to which a test measures what it claims, or purports, to be measuring ." In the classical model of test validity, construct validity is one of three main types of validity evidence, alongside content validity and criterion validity . Modern validity theory defines construct validity as the overarching concern of validity research, subsuming all other types of validity evidence . </P> <P> Construct validity is the appropriateness of inferences made on the basis of observations or measurements (often test scores), specifically whether a test measures the intended construct . Constructs are abstractions that are deliberately created by researchers in order to conceptualize the latent variable, which is correlated with scores on a given measure (although it is not directly observable). Construct validity examines the question: Does the measure behave like the theory says a measure of that construct should behave? </P>

The ability of an instrument of actually measure what it is intended to measure is known as