MCQ TESTING
Benha Faculty of Medicine
Dermatology & Andrology Department
Undergraduate Exam
January 2007 Time allowed 45 min
Why MCQs?
• Test a wide range of issues
• Not affected by a student's ability to write
• Fair marking
• Quickly marked by computer
• Computer gives analysis
of questions
• A bank of questions can be built up
• Can be used for quick revision
Weaknesses
of MCQ tests
• They do not test synthesis
• Time-consuming
• Student's must select from your alternatives
• Guessing may result in 20-25% right answers
• Attention to security
• Questions need to be pre-tested
Anatomy
of an MCQ
Impetigo is caused by:
1-Fungi
2-Parasites
3-Viruses
4-Bacteria
OPTIONSDISTRA-CTORS
ANSWER
STEM
Before writing
1- Find who's your audience
• Tailor the topics and difficulty of questions to the goals of the course
• Be sensitive to cultural and gender issues
2-Test for significant learning outcomes
• Knowledge Recalling information
The outermost layer of the epidermis is the: 1-Malpighian layer 2-Basal layer 3-Horny layer 4-Granular layer
• Comprehension
Understanding the meaning of information
Syphilis in pregnancy can be treated by the following drugs EXCEPT:
1-Penicillin 2-Tetracyclins 3-Macrolides 4-Cephalosprins
• Application Solving a problem or making a decision
A diabetic patient with pemphigus
vulgaris should be given:
1-10-20 mg prednisolone/day
2-20 mg triamcinolone/day
3-Cyclophosphamide100-200mg/day
4-Acitratin 25 mg/day
3-Ask questions on
important aspects of
the topic
4-Focus on common student mistakes
e.g. griseofulvin in tinea versicolor
5-Do not give away answers to a previous question with a later question
6-Inform the examinees about the source of your questions
Writing The Stem
1-Determine the point to be tested
2- Avoid dealing with more than one problem
• In tinea capitis the best systemic treatment is:
• In eczematized tinea capitis the best systemic treatment is:
3-Avoid including words that do not contribute to the basis for choosing between options
Acne is a troublesome disease. Some drugs used in its treatment are dangerous during pregnancy e.g.:
Which of the following drugs is contraindicated in pregnant women with acne:
4-Include as much information in the stem and as little in the options as possible
A condition in which a man is unable to have an erection firm enough for intromission and copulatory movements till ejaculation is called:
ED is defined as:
5-Avoid negative questions
e.g. which one is NOT an antifungal?
• If this cannot be avoided, negative words should be: highlighted or in bold or in capitals
Which of the following drugs is NOT used in the treatment of ….
Writing The Options
1- Restrict the use of terms such as "always" or "never" in options (they are very rarely true)
2-Three or four well constructed options are enough. Generally, the minimal improvement to the exam due to adding a fifth option is not worth the effort to construct it
3- Avoid "All of the above"
(one recognized distractor eliminates it )
These drugs are antiscabitic :
1-Ectomethrine
2-Penicillin
3-Digitalis
4-All of the above
4- “None of the above" is acceptable if the question is factual
The pudedal artery is a branch from:
It is probably desirable if computation yields the answer
The dose of isotretinoin in a 60 kgm acne patient is :
5- Vary the location of the answer on as random a basis as possible. Students know that for some examiners the first option is rarely the answer
6-List the options in a logical order, e.g. if there are numbers the options should be arranged in ascending or descending order
7-Avoid grammatical cues i.e. one or more distractors don’t follow grammatically from the stem
A patient with itching that increases by night, a positive family history and penile itchy papule:
1-Have scabies 2-Has lichen planus
3-Is atopic
8-Options should be homogeneous
Crusts can be found in:
1-Ecthyma
2-Psoriasis
3-Lichen planus
4-ED
9-Distractors should be equally plausible to a weak candidate
10-Do not repeat information in all the options needlessly
Rifampicin in leprosy treatment :
1-Should be given as a 300mg dose once monthly
2-Should be given as a 600mg dose once monthly
3-Should be given as a 900mg dose once monthly
11-Have a colleague with expertise in the contents of the exam review the items
Marking
The Optical Mark Reading Scanner
• Students record their answers on a machine readable answer sheet
• These sheets are fed through an Optical Mark Reading Scanner that turns pencil marks into useable computer information
• If two or more circles are filled in on the answer sheet, the question will be marked 'wrong‘
• Specially written software controls the test scoring and analysis
Negative(formula)
marking:
To use or not to use?
Marks are subtracted every time an incorrect option has been selected
Theoretically, negative marking is intended to discourage guessing
The largest systematic study comparing right scoring and negative marking showed that using right scoring produced slightly higher scores than formula scoring
Disadvantages of negative scoring
• It takes examinees longer
• The directions are more complicated
• It might discourage answering based on good partial knowledge
• May actually penalise the better students who might be less likely to give educated guesses
Questions Evaluation
Does a question discriminate well
between examinees?
1-Questions answered correctly by nearly all examinees are useless for discriminating among students
2-Questions answered correctly by more than 85%of students have markedly reduced power to discriminate
3- Distractors that are not chosen by any examinees should be replaced
Measuring Discremination Index
ordering the test scores from lowest to highest ordering the test scores from lowest to highest
1-Arrange test scores from lowest to highest
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2-Separate these scores into four equal parts
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Lower quartile
Upperer quartile
3-Determine Ch and Cl
• Ch : No. of students who answered this question correctly in the high performing group
• Cl : No. of students who answered this question correctly in the low performing group
4-Calculate Discrimination Index for each group
Discrimination Index= (Ch - Cl)
Nh or Nl
Nh=No.of students in the high
performing group
Nl=No. of students in the low
performing group
The bigger the discrimination index for a question, the better its ability to dicriminate among students:
• Excellent: > 0.35
• Good: 0.35 - 0.25
• Acceptable: 0.25 - 0.15
• Deleted: < 0.1
Estimation of a Question Difficulty
• Easiness= Total No. of correct answers No. of students who took the test
• Difficulty = 1 – easiness
Too difficult <0.3 Too easy >0.7
Estimation of test difficulty is useful because:
• It can help determining passing score
• It gives experience in writing exams in the future