Types of Validity in Educational Assessment and Evaluation

Validity in assessment is the degree to which an assessment instrument measures what it is intended to measure. It also refers to the usefulness of the instrument for a given purpose. It is the most important criterion of a good assessment instrument.

There are ways of establishing (types of) validity.

FACE VALIDITY

Face validity is the physical appearance of the instrument. Is the instrument, if written, easy to read for the students? Are there smears or eye-irritating lines that can distract the test-takers?

CONTENT VALIDITY

Content validity is done through a careful and critical examination of the objectives of assessment so that it reflects the curricular objectives. Is the testing emphasis parallel to the teaching emphasis?

CRITERION VALIDITY

Criterion validity is established statistically (i.e. by the use of statistical tools) such that a set of scores revealed by the measuring instrument is correlated with the scores obtained in another external predictor of measure. Criterion validity has two purposes:

a. Concurrent Validity describes the present status of the individual by correlating the sets of scores obtained from two measures given concurrently.
b. Predictive Validity describes the future performance of an individual by correlating the sets of scores obtained from two measures given at a longer time interval.

CONSTRUCT VALIDITY

Construct validity is, like criterion validity, established statistically (i.e. by the use of statistical tools). However, this time, for construct validity, statistical data are compared using psychological traits or factors that theoretically influence scores in a test.

There are two types of construct validity:

a. Convergent Validity is established if the instrument defines another similar trait other than what it is intended to measure. For example, we have Critical Thinking Test may be correlated with Creative Thinking Test.
b. Divergent Validity is established if an instrument can describe only the intended trait and not the other traits. For example, we have Critical Thinking Test may not be correlated with Reading Comprehension Test.