In psychometrics, criterion or concrete validity is the extent to which a measure is related to an outcome. Criterion validity is often divided into concurrent and predictive validity. Concurrent validity refers to a comparison between the measure in question and an outcome assessed at the same time. In Standards for Educational & Psychological Tests, it states, "concurrent validity reflects only the status quo at a particular time."Predictive validity, on the other hand, compares the measure in question with an outcome assessed at a later time. Although concurrent and predictive validity are similar, it is cautioned to keep the terms and findings separated. "Concurrent validity should not be used as a substitute for predictive validity without an appropriate supporting rationale."
An example of concurrent validity is a comparison of the scores of the CLEP® College Algebra exam with course grades in college algebra to determine the degree to which scores on the CLEP are related to performance in a college algebra class. An example of predictive validity is a comparison of scores on the SAT™ with first semester grade point average (GPA) in college; this assesses the degree to which SAT scores are predictive of college performance.