Validity is the extent to which a test measures what it claims to measure. It is vital for a test to be valid in order for the results to be accurately applied and interpreted. Validity isn’t determined by a single statistic, but by a body of research that demonstrates the relationship between the test and the behavior it is intended to measure. There are three types of validity: 1. Content Validity When a test has content validity, the items on the test represent the entire range of possible items the test should cover. Individual test questions may be drawn from a large pool of items that cover a broad range of topics. In some instances where a test measures a trait that is difficult to define, an expert judge may rate each item’s relevance. Because each judge is basing their rating on opinion, two independent judges rate the test separately. Items that are rated as strongly relevant by both judges will be included in the final test. 2. Criterion-related Validity A test is said to have criterion-related validity when the test has demonstrated its effectiveness in predicting criterion or indicators of a construct. There are two different types of criterion validity: Concurrent Validity occurs when the criterion measures are obtained at the same time as the test scores. This indicates the extent to which the test scores accurately estimate an individual’s current state with regards to the criterion. For example, on a test that measures levels of depression, the test would be said to have concurrent validity if it measured the current levels of depression experienced by the test taker. Predictive Validity occurs when the criterion measures are obtained at a time after the test. Examples of test with predictive validity are career or aptitude tests , which are helpful in determining who is likely to succeed or fail in certain subjects or occupations. 3. Construct Validity A test has construct validity if it demonstrates an association between the test scores and the prediction of a theoretical trait. Intelligence tests are one example of measurement instruments that should have construct validity.
Validity is the extent to which a test measures what it claims
to measure. It is vital for a test to be valid in order for the
results to be accurately applied and interpreted.Validity isnt
determined by a single statistic, but by a body of research that
demonstrates the relationship between the test and the behavior it
is intended to measure. There are three types of validity:1.
Content ValidityWhen a test has content validity, the items on the
test represent the entire range of possible items the test should
cover. Individual test questions may be drawn from a large pool of
items that cover a broad range of topics.In some instances where a
test measures a trait that is difcult to defne, an expert judge may
rate each items relevance. Because each judge is basing their
rating on opinion, two independent judges rate the test
separately.Items that are rated as strongly relevant by both judges
will be included in the fnal test.2. Criterion-related ValidityA
test is said to have criterion-related validity when the test has
demonstrated its efectiveness in predicting criterion or indicators
of a construct. There are two diferent types of criterion validity:
Concurrent Validity occurs when the criterion measures are obtained
at the same time as the test scores. This indicates the extent to
which the test scores accurately estimate an individuals current
state with regards to the criterion. For example, on a test that
measures levels of depression, the test would be said to have
concurrent validity if it measured the current levels of depression
experienced by the test taker. Predictive Validity occurs when the
criterion measures are obtained at a time after the test.
Examplesof test with predictive validity are career or aptitude
tests, which are helpful in determining who is likely to succeed or
fail in certain subjects or occupations.3. Construct ValidityA test
has construct validity if it demonstrates an association between
the test scores and the prediction of a theoretical trait.
Intelligence tests are one example of measurement instruments that
should have construct validity.
