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Questionnaires: Making questions answer questions
Sir Francis Galton, F.R.S. is known as the father of the questionnaire. He was also a half-cousin of Charles Darwin, an English Victorian polymath, anthropologist, eugenicist, tropical explorer, geographer, inventor, meteorologist, proto-geneticist, psychometrician, and statistician.
How to analyze
WhenWhat Kind
One Best
Source
The British Medical Association, considered one of the most authoritative research organizations, publishes a peer-reviewed journal called BMJ (formerly British Medical Journal).
In 2004 BMJ published a series entitled "Hands-on guide to questionnaire research“.
When to Use Research
Questionnaires
Best Method of Data Collection for Chosen
Subject?• Pre-requisites for using questionnaires:
– Well defined concept of what information you actually want to collect
– A good grasp of the topical territory
• When a questionnaire is not the best method
– http://www.bmj.com/cgi/content/full/328/7451/1312/DC1#a
Standardization• Meaning of “Standardized”
questionnaire:– Identical questions– Identical format– Identical response recording process
• Standardization creates reliability– Do not use a non-standardized
questionnaire unless you want unreliable results
Can You Use Existing Designs?
Published, authenticated questionnaires are invaluable:– Already standardized.
– Allow comparison of your findings with other studies that used the tool.
– Saves time of having to design and test a new questionnaire.
http://www.bmj.com/cgi/content/full/328/7451/1312?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&
fulltext=Boynton+PM%2C+Wood+GW%2C+Greenhalgh+T.+Hands-on+guide+to+questionnaire+research%3A+reaching+beyond+the+white+middle+classes&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT
How Reliable is the Design?
• Participants answers may not reflect reality– Example: Self-completed questionnaires on
dessert intake only measure what participants say they have ingested not what has actually been consumed.
• Must account for original context of questionnaire– Time period– Culture– Country, etc.
Types of questionsOpen questions: answers not preset; allow participants to create own responses
Closed: give participants options e.g. check boxes, mark a scale, select an answer from list, etc.
Pros and ConsOpen questions:• pros: potentially unlimited range of answers• cons: more difficult to translate into data--
takes a lot more time and effort to do
Closed questions:• pros: easy to convert answers to empirical
data• cons: can be frustrating to participants,
potential range of answers limited by researchers
Types of closed
questions1.Statements
with tick box categories □ yes □ no
Please check the box that best agrees with your answer
2. Numerical Rating Scales
4 3 2 1 Please indicate
how convenient you find our new hours
3. Visual analogue
scales
On the line below please indicate with an X how you have reacted to your new medication
You have just received a lesson in healthy eating. Please look at the faces above and pick the one that best symbolizes how you feel about this advice.
4. Symbols
Before beginning study:Budget both time and moneyAgree on program and coding
system
“It’s better to have fewer good quality responses than a high number that are inaccurate or incomplete.”
Analysis
Descriptive
Statistics ☛ Averages, Ranges, Ratios
X # said X
☛ Complex comparisons
Inferential Statistics
Spearman's rank-order correlation.
Pearson's coefficient of correlation
Chi-square distribution
Simple interrelationships
Analysis of Variance (ANOVA) multiple variables can be tested at the same time : 3 or more variants can be analyzed simultaneously with a pivot table
Multivariant analysis
♀ responded X
♂ responded X
Methods section1. Details of exclusions
2. Data on refusal/unsuitable3. State and justify statistical analysis used
1. Ensure results are hypothesis driven2. Report non-significant results
Results section
1. Suggest what findings mean2. Acknowledge limitations3. Discuss the questions participants
refused to answer or answered in an unpredictable manner
Discussion section
The End ?
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