Test validity is an indicator of how much meaning can be placed upon a set of test results. In psychological and educational testing, where the importance and accuracy of tests is paramount, test validity is crucial.
Content validity establishes how well a test compares to the real world. For example, a school test of ability should reflect what is actually taught in the classroom.
Criterion validity establishes whether the test matches a certain set of abilities.
Concurrent validity measures the test against a benchmark test, and highcorrelation indicates that the test has strong criterion validity.
is a measure of how well a test predicts abilities, such asmeasuring whether a good grade point average at high school leads to good results at university.
Construct validity is a measure of how well a test measures up to its claims. A test designed to measure depression must only measure that particular construct, not closely related ideals such as anxiety or stress.
Face validity is an estimate of the degree to which a measure is clearly and unambiguously tapping the construct it purports to assess. Thus, face validity refers to the “obviousness” of a test—the degree to which the purpose of the test is apparent to those taking it. Tests wherein the purpose is clear, even to naïve respondents, are said to have high face validity ; tests wherein the purpose is unclear have low face validity (Nevo, 1985).