Do choice-type tests (multiple-choice, true-false, etc.) measure the same abilities or traits as free response (essay, recall, completion, etc.) tests? A large number of studies conducted with several different methodologies and spanning a long period of time have addressed this question. In this review, attention will be focused almost exclusively on the measurement of the traditional product of education, namely knowledge. This review is limited to empirical studies of the equivalence of free-response and choice-type tests. The major methods used to study the relationship between free-response and choice-type measures are the direct correlation, the criterion correlation and the treatment effect. Contrary to widely held beliefs about choice-type tests, the studies indicate that the two types of tests do generally measure the same traits or abilities. To the extent that there are minor differences, the choice-type measures tend to be more valid; and use of choice-type measures does not seem to have adverse effects on study habits. However, the generalizations are limited by insufficient diversity in the groups studied and may not apply to certain types of more divergent processes. Aspect of National Assessment (NAEP) dealt with in this document: Assessment Instrument (Multiple Choice Exercises) (Open Ended Exercises). (Author/PN)