Transcript Slide 1
Research Methods
Unit 9
What is the Scientific Method?
Scientific Method: A specific set of
procedures used by scientists trying to
prove an idea.
Hypothesis: The specific question being
asked by research, or a prediction of the
outcome of a study.
What is the Scientific Method?
Types of Data
Quantitative Data: Data that is
measurable using scientific methods, and that
can be manipulated using mathematical
equations.
◦ Example: People who have a certain height,
and a certain weight, can be calculated as
having a certain BMI.
Qualitative Data: Data that is not
measurable using scientific methods and
cannot be manipulated using mathematical
equations.
◦ Example: Descriptions of patient behaviors.
Measurements
If you use any type of assessment or
measurement (e.g., a test or survey) you
must make sure it has two things….
Validity: Whether the instrument
measured what it was intended to
measure.
Reliability: Whether the instrument will
measure the same basic score across
repeated testings.
Research Design
Research Design determines whether
the study is going to be experimental
or correlational.
Correlational studies show that a
relationship already exists between A and
B.
Experimental studies are designed to
show that A causes B.
Correlational Design
Correlational Studies are designed to
examine an existing relationship between
two variables.
◦ Researchers DO NOT manipulate any
variables!
CORRELATION DOES NOT
EQUAL CAUSATION!!!!!
◦ We are only evaluating a relationship that
ALREADY exists!
Correlational Design
Positive
Correlation
: The
variables
move
together
along the
graph.
◦ If one
increases, the
other
increases.
Correlational Design
Negative
Correlation
: The
variables
move
opposite to
each other
along the
graph.
◦ If one
increases, the
other
decreases.
Correlational Design
Correlation is designated as an r score.
◦ Correlations range from -1 to +1.
The closer to 1 the score is, the
stronger the correlation.
◦ R = 0.98 is strong!
The closer to 0 the score is, the weaker
the correlation.
◦ R = 0.01 is weak!
Correlational Design
Experimental Design
Groups: At least one experimental and one
control.
◦ Experimental Group: This group receives whatever
treatment is being studied.
◦ Control Group: This group goes through every step
of the research study that the experimental group
goes through, but does not receive the treatment.
When we evaluate data, we compare the results
of the experimental and control groups.
◦ If there is a change in the experimental group but not
control, then the results are not due to chance.
◦ If there is a change in both groups, it probably isn’t
due to your treatment.
Experimental Design
Variables: Factors that will be measured when
conducting an experiment.
◦ Examples: Weight, gender, height, eye color, etc.
Independent Variable: The variable that is actively
affected by the “treatment” in the study.
Dependent Variable: The variable being measured
to determine if the independent variable had an effect
on the subject.
Example: Pain control using Morphine.
◦ Independent Variable: Amount of morphine given.
◦ Dependent Variable: The amount of pain the
patient reports after receiving pain management.
Experimental Design
Experimenter Bias: A condition where
the researcher has affect on the outcome
of the study.
◦ Can be intentional or unintentional.
Research Methods
Once you decide whether you are
collecting experimental data or evaluating
correlational relationships, we must
decide HOW we are going to look at the
problem!
Case Studies
Case Study: An in-depth study of one or
a small number of individuals.
◦ Data is typically qualitative.
Observational Studies
Observational Studies: Studies that
involve observing and possibly measuring
behaviors or characteristics of a subject.
Observational Studies
Laboratory Observation: Observation
that occurs in a laboratory setting under
controlled conditions.
Observational Studies
Naturalistic Observation: Observation that
occurs in a natural setting where behavior and
conditions are not controlled.
◦ Direct/Declared Observation: Those being
observed are aware that they are part of a study and
are being observed.
◦ Undeclared/Indirect Observation: The
researcher is not hidden, but does not allow the
subjects to be aware they are being observed for the
purpose of a study.
◦ Participant Observation: The researcher
integrates themselves into the lives of those being
observed.
Can be declared or undeclared.
Surveys
Survey: A series of questions designed
to learn a considerable amount about a
variety of potential topics.
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Personal characteristics or preferences
Life experiences
Attitudes
Opinions
Behaviors
Education level
Etc.
Surveys
Can be used to supplement other
research data (e.g. demographic
information)
Can be in a variety of formats..
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Fill-in-the-blank
Multiple choice
Written answer/Paragraph answer
Oral/Spoken Response/Interview
Surveys
The downside:
◦ Can be expensive to print and mail
◦ Long-distance phone calls get expensive
◦ Could end up in a bad part of town doing
interviews
◦ Only around 10% of surveys end up returned
If you want 100 answers, you have to send out
1,000 surveys!
At $0.42 per stamp to send, plus a stamp to return,
that makes $840 just in stamps!!!!!
Choosing Participants
Population: A group of individuals with certain
characteristics in common.
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Age
Race
Language
Religion
Geographic Location/Area
Education level
Career/Field
Confounding Factors: Something particular to
a participant that may potentially interfere with
your study/data interpretation.
Choosing Participants
Random Sampling: Choosing
individuals using some sort of random
method that ensures participants are not
picked based on any particular traits or
characteristics.
◦ Example: Putting every potential population
members’ name in a hat, then picking at
random.
Choosing Participants
Systematic Random Sampling:
Choosing the participants in some way
that is random, but still has a set pattern.
◦ Example: Every 5th name in the phone
book.
Choosing Participants
Stratified Random Sampling: Dividing
the population into sub-groups, then using
a random sampling method to select
individuals from each group.
◦ Example: Dividing a population of
“medical workers” into techs, medics,
LPNs, RNs, Pas, Drs, etc., then selecting
10 of each.
Choosing Participants
Quota Sampling: Dividing the
population into sub-units as in Stratified
Random Sampling, then selecting a specific
number from each sub-group.
◦ Example: Dividing population into male and
female groups, then selecting exactly 200 men
and 300 women for data.
◦ PROBLEM: NOT RANDOM!
Choosing Participants
Matched Random Sampling: Analyzing
the characteristics of the population being
studied, then ensuring that each known
characteristic is “matched” across all groups.
◦ Example: If a participant comes in with an IQ of
115 and is placed in Group A, the next participant
with an IQ of 115 would go in Group B, and so
on, until all groups had one individual with an IQ
of 115.
BEST METHOD for preventing
CONFOUNDING FACTORS
Choosing Participants
Convenience Sampling: Selecting an
individual to participate in a study
because they happen to be at hand or
convenient to get to participate.
◦ Example: When I do research at Austin Peay,
I convince friends that teach there to offer
their classes extra credit to participate.
◦ Problem: IT’S NOT RANDOM AT ALL!
Length of the Study
Longitudinal Design: Follows the same group
of individuals for an extended period of time.
◦ Example: 7UP documentary series followed a group
of individuals in England from the age of 7 to 47 in a
series of filmed interviews.
◦ Advantages:
You can determine if characteristics are stable across
time - Developmental trends can be observed
◦ Disadvantages: Attrition, cost, multiple
researchers might be needed.
Attrition:The process of participants leaving a study
before completion.
Death, illness, loss of interest, inconvenience, moved away, etc.
Length of Study
Cross-Sectional: Attempts to study a
particular trait relatively quickly, so matches
participants with similar characteristics into
multiple age groups.
◦ Example:The 7UP series could have been
filmed all at once with a separate group of
individuals for each age range.
E.g. a group of 7-14, a group of 15-25, a group of
25-35, a group of 35-47, etc.
◦ Advantage: Much faster research time!
◦ Disadvantages: Possible cohort effects.
Example: There might be something special
about individuals who were alive during WWII,
compared to those at a younger age.
Length of Study
Sequential Research: A blend of
longitudinal and cross-sectional design.
◦ Follows multiple groups for a length of
time sufficient to tell if the results are due
to a confounding factor or cohort effect.
◦ Example: Instead of groups of 10-20, 20-30, and
30-40 studied for one year, each group could be
studied for 20 years.
We would see longitudinal data of the 10 year
olds becoming the 30 year old group by the end.
◦ Advantages: Longitudinal developmental data
available at a much quicker and cheaper rate.
Ethics
Institutional Review Board (IRB): A
special panel at all major universities that
determine if research is allowed to occur.
◦ Decision is based on cost-benefit analysis: Is
what we can learn from the research worth
the potential risk of harm to the participants?
Ethics
Privacy:
◦ All data that could be potential incriminating
must be kept separate from the names and
demographic information of a participant so that
they could not be identified if the data were
published.
◦ All results must be kept confidential and only
discussed with other researchers, NEVER using
identifiable information.
◦ Example: Tornado of 1999, professors at APSU
seen chasing papers across the quad to collect
potentially incriminating surveys regarding drug
use.
Ethics
Informed Consent: All research participants
must sign a document stating that they
understand all potential risks for participating in
the study.
◦ Example: Mrs. Mayo’s Training Studying
Our goal: Determine if someone can learn to fold an
Origami penguin better if they watch someone in
person, watch a video, or read paper instructions.
Austin Peay’s IRB decided we must inform them…
You could receive a paper cut, so we will have non-latex
bandages and a variety of antibiotic creams available.
You could become frustrated if you can’t fold the penguin
right, so we will provide assistance in finishing and access to a
licensed counselor to talk to.
Ethics
Deception: The process of not telling
the participant something regarding the
study to prevent them either intentionally
or unintentionally altering the results.
◦ Deception is only used if the researcher can
prove that a participant knowing the goal
could potentially damage the results.
◦ The participant must undergo debriefing
immediately afterword to inform them of the
deception.
Ethics
Examples of Deception used when testing a
new medication:
◦ Blind Studies: The patient doesn’t know if
they’re receiving a placebo or the new
medication.
◦ Double-Blind Studies: Neither the patient nor
the doctor know whether the new medication or
a placebo are being used.
◦ Triple-Blind Studies: The patient, the doctor,
and the researcher bringing the meds to the
doctor all are in the dark as to whether it is the
new med or placebo.