Multiple-Choice Tests

A multiple-choice test usually has dozens of questions or "items." For each question, the test- taker is supposed to select the "best" choice among a set of four or five options. (They are sometime called "selected-response tests.") For example:

What causes night and day?

A. The earth spins on its axis.
B. The earth moves around the sun.
C. Clouds block out the sun's light.
D. The earth moves into and out of the sun's shadow.
E. The sun goes around the earth.

(Source: P. M. Sadler, "Psychometric Models of Student Conceptions in Science," Journal of Research in Science Teaching (1998. V. 35, N. 3, pp. 265-296).)

The "wanted" answer is "A." The other answer options are called "distractors."

Most standardized tests, including state exams and most commercial achievement tests, are made up primarily of multiple-choice items. A few state tests have a quarter, a half or even more "open-ended" (or "constructed-response") items, usually short answer questions. These ask a student to write and perhaps explain, not just select, an answer. Many short-answer questions are not much more than multiple-choice items without the answer options, and they share many of the limits and problems of multiple-choice items.

Are multiple-choice tests "objective"?

Test-makers often promote multiple-choice tests as "objective." This is because there is no human judgement in the scoring, which usually is done by machine. However, humans decide what questions to ask, how to phrase questions, and what "distractors" to use. All these are subjective decisions that can be biased in ways that unfairly reward or harm some test-takers. Therefore, multiple-choice tests are not really objective.

Any uses of test results involve additional human decisions, including such things as setting a "cut-off" or passing-level score on a test. Some people also claim multiple-choice tests avoid the subjective views of any one teacher, who may be biased or have low expectations. This is true, but there are many ways to address these problems, such as by having independent groups of teachers and others review student essays, projects, portfolios or other more comprehensive forms of assessment.

What can multiple-choice items be used for?

Multiple-choice items are best used for checking whether students have learned facts and routine procedures that have one, clearly correct answer. However, an item may have two reasonable answer options. Therefore, test directions usually ask test takers to select the "best" answer. If, on a reading test, a student selected a somewhat plausible answer, does it mean that she cannot read, or that she does not see things exactly the way the testmaker does?

In some subjects, carefully written multiple-choice items with good distractors can fairly accurately distinguish students who grasp a basic concept from those who do not. Look again at the "night and day" question. Those who don't quite get it often are attracted by answer B. Those who have little or no knowledge usually select C, D or E.