Rodriguez writes, “I would support this advice by contributing the concern that in most cases, only three are feasible. Based on this synthesis, MC items should consist of three options, one correct option and two plausible distractors. Using more options does little to improve item and test score statistics and typically results in implausible distractors. The role of distractor deletion method makes the argument stronger. Beyond the evidence, practical arguments continue to be persuasive.
- Less time is needed to prepare two plausible distractors than three or four distractors.
- More 3-option items can be administered per unit of time than 4- or 5-option items, potentially improving content coverage.
- The inclusion of additional high quality items per unit of time should improve test score reliability, providing additional validity-related evidence regarding the consistency of scores and score meaningfulness and usability.
- More options result in exposing additional aspects of the domain to students, possibly increasing the provision of context clues to other questions (particularly if the additional distractors are plausible).”