Criterion Validity:
The criterion validity of survey instruments, like the tests used in psychometrics , is a measure of agreement between the results obtained by the given survey instrument and more "objective" results for the same population. The "objective" results are obtained either by a well established instrument ("the gold standard") or by direct measurement. The criterion validity may be quantified by the correlation coefficient between the two sets of measurements.
Depending on the nature of the reference data set, the criterion validity measures are subdivided into concurrent validity and predictive validity measures.