Multiple choice questions

Multiple choice questions (MCQs) can be excellent tools for self learning-learning allowing individuals to identify areas of their knowledge which is weak, as well as allowing the development of metrics to compare oneself with other individuals of a similar level. To achieve thisThey are also extensively used in assessment during medical training.

For questions to be useful, however, questionsthey need to be well written and adhere to a number of best practices.  

MCQs are coming to Radiopaedia.org very soon (stay tuned)

This article covers a number of aspects of this topic as it relates to Radiopaedia.org, including terminology and best practices. 

Terminology 

An MCQ has a number of parts: 

1. stem:this is the first part of the question, typically contains the most words
2. lead in: follows the stem, and often phrased as aleads into the alternatives and makes it obvious what is being asked of the examinee in this question. 
3. alternatives (or options):these are usually shorter and offer various options to choose from to answer or complete the stem. 
   • answer (or key): this is the alternative that is correct
   • distractor: these are alternatives (usually 3 or 4) that are incorrect

Best practices 

If aan MCQ is to be useful it needs to be clear and concise. It can test factual knowledge or require thinking, but for the purposes of Radiopaedia.org, it should be primarily about comprehending the question. The following rules should be followed when authoring questions. 

Stem

Clarity

• clear: the stem should be clearly written, and unambiguous; do not try and trick the examinee
• short: try and keep the stem as short as possible without diminishing comprehension
• avoid negatives
  • in most instances, stems should be worded to achieve a positive / true answer as this reinforces knowledge. 
    • correct: "In what demographic is MS most common?" 
    • incorrect: "In what demographic is MS least common?"
  • sometimes the learning goal is a negative answer, but this is uncommon
• avoid double negatives: double negatives are never needed and should be avoided

Lead in

The lead in follows the stem and is used to instruct the examinee as to exactly what is required to answer the question correctly. It can either be in the form of a question or a phrase needing completion. 

• question: "What is the most likely diagnosis?"
• completion: "The third branch from the arch of the aorta is..."

It is essential that for the completion type lead in, that the alternatives (see below) are phrased in such a way that they grammatically finish the lead in appropriately – in other words, you should be able to read the lead in + alternative and it should make sense. 

Alternatives

Length and content

• short:
  • alternatives should be as short as possible with the majority of the text in the stem
  • if a term is going to be repeated in each alternative, then it should be moved into the stem or lead in
• similar in length: alternatives
  • should all be approximately the same length and
  • have similar language and grammar to avoid inadvertent clues
• similar content: the alternatives
  • should be similar so that noin content and phrasing to avoid one alternative clearly is the odd-one-out;
  • if homogeneity of answers is not possible then have a similar number of alternative for each type (balanced)
• similar scale:
  • if numbers are used in the alternatives, they should all be in the same unit of measure
• non-overlapping ranges
  • avoid overlapping numeric or verbal ranges  i.e. 0-5, 5-10 (5 is repeated). Instead, use 0-5, 6-10.
• balanced alternatives
  • If 3 alternatives have the word aorta in it, then you probably need 3 other alternatives with a repeated word to ensure that no clue is present

Order

• alphabetical: when similar alternatives

  Alternatives should be presented in alphabeticala non-random order

• increasing: when numeric. This not only reduced cognitive effort in parsing the alternatives but also enforces a more random selection of the correct answer. 

  For sets of alternatives that have a natural order, this

  should be in ascending order (e. Examples include:
  • values: e.g. 2, 6, 8, 12), 20
  • randomranges: if the alternatives do not lend themselves to alphanumeric ordering (thise.g. 0-5, 6 -10, 11-15
  • density/intensity: e.g. hypodense, isodense, hyperdense
  • anatomic: e.g. T1, T2, T3, T4, T5

  When no such natural order exists, then answers should be rare) then try to be random as to which alternative is the correct answer

Avoid

• compound answers: alternatives such a "B & C" or "A, B and D" are to be avoided
• all or none of the above: it is generally better to have fewer alternatives than to add filler alternatives such as these
• silly or obvious alternatives: obviously correct or obviously incorrect answers, even if humorous, detract from learning
• clueing: the correct answer can be guessed without any actual knowledge of the topic​. Examples some types of clues to be avoided:
  • some terms repeated more often in than others
  • use of 'never' or 'always'
  • repeating words from the stem

Related article

Each MCQ will be linked to aat least one 'related article' which. Each alternative (see above) should have a relevant article; in many instances, all five alternatives will have just the one related article, whilst at other times 5 related articles will be needed. A related article to a distractor is not only ok, it is encouraged. 

This has a number ofmany functions: 

1. Provideprovide further reading on the topic.
2. Directlydirectly support the answer with appropriate references in the article.
3. Will also link the MCQ to an article and therefore allow the question to inherit all sorts of attributes (e.g. system) and knowledge of where it fits into the greater scheme of things. 
4. allow the question to be viewed from the related article