Medical Education
Multiple choice questions:
A literature review on the optimal number of options
RASHMI VYAS, AVINASH SUPE
ABSTRACT
Background. Single, best response, multiple choice questions
(MCQs) with 4 options (3 distractors and 1 correct answer) or
5 options (4 distractors) have been widely used as an assessment
tool in medical education in India and globally. Writing plausible
distractors is time consuming and the most difficult part of
preparing MCQs. If the number of options can be reduced to 3,
it will make preparing MCQs less difficult and time consuming,
thus reducing the likelihood of flaws in writing MCQs. We
reviewed the literature to find out if the number of options in
MCQ test items could be reduced to 3 without affecting the
quality of the test.
Methods. A systematic database search was done using the
following question as a framework: How many options are
optimal for multiple choice questions? Theoretical, analytical
and empirical studies, which addressed this issue, were included
in the review.
Results. There was no significant change in the psychometric
properties of the 3 options test when compared with 4 and 5
options. MCQs with 3 options improved the efficiency of the test
as well as its administration compared with 4- or 5-option MCQs.
MCQs with 3 options had a higher efficiency because fewer
distractors needed to be prepared, took up less space and
required less reading time, decreased the time required to
develop the items and the time to administer, and more items
could be administered in a given time thus increasing the content
sampled.
Conclusion. Our review of the literature suggests that MCQs
with 3 options provide a similar quality of test as that with 4- or
5-option MCQs. We suggest that MCQs with 3 options should
be preferred.
Natl Med J India 2008;21:130–3
INTRODUCTION
Multiple choice questions (MCQs) are used globally as test items
for assessment in various fields of education.
1–4
In India, MCQs
have been commonly used for undergraduate and postgraduate
medical entrance and university examinations.
5–8
These are also
used as an assessment tool for paramedical courses and formative
assessment in the medical curriculum.
9–11
The main challenge in preparing MCQs is to construct good
test items.
12–15
This requires a good knowledge of the content and
understanding of the objectives of assessment as well as good
skills in writing the items.
15–17
Though there are many guidelines
for writing good test items,
18–21
these are usually not adhered to;
leading to the preparation and administration of faulty MCQs.
8,22,23
The single, best-response type MCQ (the format that asks the
student to choose the best answer from a list of possible answers)
with 4 or 5 options is the most commonly used format.
14,22,24–28
For
a distractor (wrong option) to be useful, it should represent a
common misconception among students about the correct answer.
26
Writing plausible distractors is time consuming and the most
difficult part of preparing MCQs.
17,26,29,30
Some of the main flaws
in writing distrators include implausible distractors, more than
one or no correct answer, the longest option being correct, and the
use of ‘all of the above’ and ‘none of the above’ options.
22,23
Lack
of training of the faculty in preparing MCQs and lack of time have
been identified as important reasons that contribute to flaws in
writing distrators/items.
1,8
Training faculty in the skills required
for writing items and reducing the number of distractors in an
MCQ could be some possible remedial measures.
We hypothesized that if the number of options in an MCQ can
be reduced to 3 from the commonly used 4 or 5, it would make
MCQ writing less difficult and less time consuming, thus reducing
the likelihood of flaws in writing MCQs. We, therefore, reviewed
the existing literature to determine if the number of options in an
MCQ can be reduced to 3 without affecting the quality of the test.
METHODS
A systematic database search was done using Science Direct,
Pubmed, Ovid and ERIC search engines for the period 1960–
2007. Specific articles were also looked for in the Sage publications,
JStor and Blackwell Synergy electronic resources. The articles
were searched using the following question as a framework: How
many options are optimal for multiple choice questions? The
search terms included the keywords: MCQ, multiple choice
questions, optimal distractors, optimal options, number of options,
number of distractors, one best response, item analysis and item
writing guidelines.
All studies that assessed the 3-option format were included in
the review. Studies not available in electronic format were excluded
from the review. The initial results were screened for pertinence,
which yielded 15 articles for reading. A review of the reference
lists identified 8 additional articles of interest.
RESULTS
Studies on the optimal number of options were grouped into
(i) theoretical and analytical studies, and (ii) empirical studies,
© The National Medical Journal of India 2008
THE NATIONAL MEDICAL JOURNAL OF INDIA VOL. 21, NO. 3, 2008 130
Christian Medical College, Vellore 632002, Tamil Nadu, India
RASHMI VYAS Department of Physiology
Seth G.S. Medical College and K.E.M. Hospital, Parel, Mumbai 400012,
Maharashtra, India
AVINASH SUPE Department of Surgical Gastroenterology
Correspondence to RASHMI VYAS; rashmifvyas@yahoo.co.in;
rashmifvyas@gmail.com