NOTES ON THE VALIDITY OF EDUCATIONAL
ACHIEVEMENT TESTS
1. An educational achievement test is one designed to measure the extent to which the
immediate goals of instruction in a particular area have been attained. Ideally, most
immediate goals of instruction are derived from consideration of ultimate goals in
such a manner that attainment of the immediate goals is a good indication that the
ultimate goals will be attained.
2. Any educational achievement test in a given area is a sample of items from a
hypothetical population of items which constitute one operational definition of the
measurable, immediate goals of instruction in that area.
3. The value of an educational achievement test may, in principle, be judged on the basis
of evidence concerning its content validity, concurrent validity, construct validity,
predictive validity or some combination of these. However, for most tests of
educational achievement, claims of validity must rest largely on evidence for content
validity. It is seldom that evidence for other types of validity is both available and
relevant.
4. The most fundamental and direct evidence of content validity is derived from detailed
examination of the test itself. The more closely the achievements a test requires are
related to the immediate objectives of instruction in the area, the greater its content
validity. Therefore, it is appropriate for a teacher, or other school personnel, to take an
educational achievement test for a particular purpose partly on the evidence provided
by this direct examination.
5. Ability to judge the content validity of a test is aided by presenting an outline of the
achievements covered by the test, by showing which items are intended to measure
each achievement covered, and by summarizing other criteria, principles and
standards which guided the test author(s) in selecting questions and writing items.
6. Since reliability is a necessary condition for validity, indices of score reliability and of
item discrimination are useful in judging the content validity of an educational
achievement test. Therefore, a test manual should summarize and interpret relevant
statistical data resulting from internal analysis of test scores and responses to test
items.
7. While it is theoretically possible to establish the validity of an educational
achievement test by comparing scores on it with subsequent measure of attainment of
the ultimate objectives of instruction, this process is ordinarily so difficult and time
consuming that it is seldom if ever attempted. Instead, the less precise, but possibly
more comprehensive, process of logical inference and subjective judgment usually
must be used.
8. The value of a subjective judgment on the validity of an educational achievement test
depends largely on the educational competence and expertise in testing of the person
making the judgment.
9. Coefficients of correlation between scores on a given test and those on alternative
measurement procedures may be useful in judging the concurrent, predictive, or
construct validity of a test, but are completely irrelevant to its content validity.
10. The degree of concurrent validity is a direct function of the size of the coefficient of
correlation between the test scores and the other measures the test is intended to
replace.
11. The degree of construct validity is a complex function of the agreement between
correlations predicted on the basis of theoretical definitions of the construct, and
correlations obtained experimentally.
12. It is necessary for a test author to present evidence concerning all four types of
validity for each educational achievement test he/she develops.
13. A test manual should summarize and interpret relevant statistical data on the relation
between scores from the test and from alternative measures of achievement in the
area, or between distributions of scores from groups know to differ with respect to the
achievement measured.