Day 2
Developing study questions
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What you just did
✔ What are you curious about?
✔ From curiosity to a hypothesis
From a hypothesis to questions
2
EPI Challenge
Master Proposal Form
Name of Team Member
________________
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Sections of Proposal Form
0. Team information
1. Health-related behavior and hypothesis
2. Exposure variable and question for survey
3. Outcome variable and questions for survey
4. Cross-sectional study design
5. Informed consent script
6. Data analysis plan
7. Considerations forinterpretation
8. Plans for study conduct
9. Survey instrument
10. Letter to Principal
4
Sections of Proposal Form
0. Team information
1. Health-related behavior and hypothesis
2. Exposure variable and question for survey
3. Outcome variable and questions for survey
4. Cross-sectional study design
5. Informed consent script
6. Data analysis plan
7. Considerations forinterpretation
8. Plans for study conduct
9. Survey instrument
10. Letter to Principal
5
Hypothesis
A hypothesis is an educated
guess about how things work.
Most of the time a hypothesis in
epidemiology is written like this:
"If [Exposure] ___, then
[Outcome]____ will happen.“
Your hypothesis should be
something that you can actually
test, what's called a testable
hypothesis. In other words, you
need to be able to measure both
“Exposure" and “Outcome."
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Criteria for a Good Question
1. It should be clear and unambiguous, written so that
its intended audience understands it.
Do you usually get a good night’s sleep?
Criteria for a Good Question
2. It should mean the same thing to everyone who
reads it. In other words, if 100 students all behave
the same way they must all select the same answer.
Typically, do you watch television five or more days a week?
Criteria for a Good Question
3. The answer options categorize and cover the
entire range of possible behavior (from complete
absence of the behavior to a maximum amount of
the behavior).
How often do you usually bring your lunch to school?
a. Never
b. 1-2 times per week
c. 2-4 times per week
d. Every day
Criteria for a Good Question
4. The time period to consider when answering a
particular question must be appropriate (long or short
enough) to capture the frequency of behavior desired.
In the past two years, have you typically eaten five
or more servings of fruits and vegetables per day?
Characteristics of a Good Question
• It should be written so that its intended audience
understands it.
• It should mean the same thing to everyone who reads it.
• The answer options must categorize and cover the entire
range of possible behavior (from complete absence of the
behavior to a maximum amount of the behavior).
• The time period to consider when answering a particular
question must be appropriate (long or short enough) to
capture the frequency of behavior desired (depending on
the information desired and the type of behavior).
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Characteristics of a Good Question
On an average school day, how many hours do you play video or
computer games or use a computer for something that is not school
work? (Count time spent on things such as Xbox, PlayStation, an
iPod, an iPad or other tablet, a smartphone, YouTube, Facebook or
other social networking tools, and the Internet.)
A. I do not play video or computer games or use a computer
for something that is not school work
B. Less than 1 hour per day
C. 1 hour per day
D. 2 hours per day
E. 3 hours per day
F. 4 hours per day
G. 5 or more hours per day
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Characteristics of a Good Question
On an average school day, how many hours do you play video or
computer games or use a computer for something that is not school
work? (Count time spent on things such as Xbox, PlayStation, an
iPod, an iPad or other tablet, a smartphone, YouTube, Facebook or
other social networking tools, and the Internet.)
A. I do not play video or computer games or use a computer
for something that is not school work
B. Less than 1 hour per day
C. 1 hour per day
D. 2 hours per day
E. 3 hours per day
F. 4 hours per day
G. 5 or more hours per day
It should mean the same thing to everyone who reads it.
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Characteristics of a Good Question
On an average school day, how many hours do you play video or
computer games or use a computer for something that is not school
work? (Count time spent on things such as Xbox, PlayStation, an
iPod, an iPad or other tablet, a smartphone, YouTube, Facebook or
other social networking tools, and the Internet.)
A. I do not play video or computer games or use a computer
for something that is not school work
B. Less than 1 hour per day
C. 1 hour per day
D. 2 hours per day
E. 3 hours per day
F. 4 hours per day
G. 5 or more hours per day
It should be written so that its intended audience understands it.
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Characteristics of a Good Question
On an average school day, how many hours do you play video or
computer games or use a computer for something that is not school
work? (Count time spent on things such as Xbox, PlayStation, an
iPod, an iPad or other tablet, a smartphone, YouTube, Facebook or
other social networking tools, and the Internet.)
A. I do not play video or computer games or use a computer
for something that is not school work
B. Less than 1 hour per day
C. 1 hour per day
D. 2 hours per day
E. 3 hours per day
F. 4 hours per day
G. 5 or more hours per day
The answer options must categorize and cover
the entire range of possible behavior (from complete absence of the behavior
to a maximum amount of the behavior).
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Characteristics of a Good Question
On an average school day, how many hours do you play video or
computer games or use a computer for something that is not school
work? (Count time spent on things such as Xbox, PlayStation, an
iPod, an iPad or other tablet, a smartphone, YouTube, Facebook or
other social networking tools, and the Internet.)
A. I do not play video or computer games or use a computer
for something that is not school work
B. Less than 1 hour per day
C. 1 hour per day
D. 2 hours per day
E. 3 hours per day
F. 4 hours per day
G. 5 or more hours per day
The time period to consider when answering a particular question must be
appropriate (long or short enough) to capture the frequency of behavior desired
(depending on the information desired and the type of behavior).
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Preparation for
Second Morning Breakout
Teams: Write your exposure question
and your outcome question
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You will have self-assessment sheets to be
sure you are meeting these criteria
• It should be written so that its intended
audience understands it.
• It should mean the same thing to
everyone who reads it.
• The answer options must categorize
and cover the entire range of possible
behavior (from complete absence of the
behavior to a maximum amount of the
behavior).
• The time period to consider when
answering a particular question must be
appropriate (long or short enough) to
capture the frequency of behavior
desired (depending on the information
desired and the type of behavior).
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Study Proposal: Section 2
2. Exposure Variable
2a. Name your exposure variable.
2b. Define your exposure variable.
2c. State the question will you ask to
measure your exposure variable.
2d. Identify the challenges you may
have getting accurate answers to
your exposure question.
2e. Describe how your team will
address these challenges.
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Study Proposal: Section 3
3. Outcome Variable
3a. Name your outcome variable.
3b. Define your outcome variable.
3c. State the question will you ask to
measure your outcome variable.
3d. Identify the challenges you may
have getting accurate answers to
your outcome question.
3e. Describe how your team will
address these challenges
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Breakout Deliverables
Fill out sections 2 and 3 in the green
proposal form
Prepare for the Gallery Walk after
Breakout.
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Benefits of Gallery Walk
Allows Opportunities to Rehearse, Practice, Consult
Resources, Get Feedback, and Refine
Hypothesis
xxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxx
X
Expoure question
xxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxx
X
Outcome question
xxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxx
X
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Gallery Walk –After Breakout Session
Hypothesis
Place your post-it on wall
location as instructed by
your Coaches
Follow the flow established
for the walk
Using small post-its, try to
thoughtfully comment on
as many hypotheses within
the timeframe
xxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxx
X
Expoure question
xxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxx
X
Outcome question
xxxxxxxxxxxxxxxxxxxxxxxx
xxxxxxxxxxxxxxxxxxxxxx
X
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From Epi Textbooks
Cross-Sectional Studies
• In a cross-sectional study, factors of exposure and outcome are
measured simultaneously.
• Information on exposure and outcome must fit into a 2x2 table.
• The main outcome measure obtained from a cross-sectional
study is prevalence
o A “yes/no” question will fit
o If using a multiple choice question, you will need a
predetermined “cut point” so there is a “higher/lower”
range to fit into the 2x2 table.
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o In this case, prevalence calculations require that the
variable is divided into those values that fall below or
above a particular pre-determined level.