Effective Multiple Choice Question Design
Effective Item Stems
The Anatomy of a Good Question
The foundation of any solid multiple-choice question isn't the options—it's the stem. A well-crafted stem presents a complete, self-contained problem. It allows a learner who knows the material to formulate an answer before they even glance at the choices. This is the gold standard of item design.
A straightforward, clear, and concise stem free from extraneous information increases a multiple-choice item’s reliability.
To check if your stem is effective, use the 'cover-up test'. It’s simple: hide the answer options. Does the stem still function as a clear question or a complete statement that demands a specific answer? If you can't figure out what's being asked without peeking at the options, the stem has failed. It's likely incomplete or poorly focused.
A common reason stems fail this test is 'window dressing'—extra, irrelevant information that clouds the core question. Imagine a question about a physics principle that starts with a long story about a high school student named Sarah getting ready for her science fair. While it might seem engaging, it forces the test-taker to sift through noise, increasing their and testing their reading skills more than their physics knowledge.
Poor stem: On a sunny Tuesday, a chef decides to bake a cake using a recipe that calls for 250 grams of flour. If the chef only has a 1-kilogram bag, how much flour is left after baking?
Better stem: A 1-kilogram bag of flour is used for a recipe requiring 250 grams. How much flour remains?
Positive and Negative Phrasing
Clarity also hinges on how you frame the question. Positively phrased stems are almost always better than negatively phrased ones. Stems that use words like NOT, EXCEPT, or LEAST are tricky. They require a mental flip-flop: the test-taker must evaluate each option, identify all the correct ones, and then select the one that doesn't fit. This is an extra, unnecessary step that can lead to errors, even when the person knows the material.
Sometimes a negative stem is unavoidable, especially when assessing safety rules or identifying misconceptions. If you must use one, make the negative word stand out. Capitalize it (NOT) or put it in bold to draw the learner's attention and reduce the chance of misreading.
| Phrasing | Example Stem | Mental Steps Required |
|---|---|---|
| Negative (Avoid) | Which of the following is NOT a primary color? | 1. Recall primary colors (red, yellow, blue). 2. Check option A (red) - it's a primary color. 3. Check option B (green) - it's not. 4. Select B. |
| Positive (Prefer) | Which of the following is a secondary color? | 1. Recall secondary colors (green, orange, purple). 2. Check options. 3. Select 'green'. |
Ultimately, a well-designed stem is unified. It asks one thing and does so with precision. By building your questions stem-first, stripping away window dressing, and preferring positive phrasing, you create assessments that measure knowledge, not test-taking tricks.
What is the main purpose of the 'cover-up test' when writing a multiple-choice question?
Extraneous, irrelevant information included in a question stem is referred to as: