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Created by:
Allison Childress MS, RDN, CSSD, LD
http://www.youtube.com/watch?v=fh
LZ2I2MaeQ
1. Title
2. Abstract
3. Introduction
4. Methods
5. Results
6. Discussion
7. References
Abstract
• A brief summary of the entire article in
approximately 120 words
• Contains a concise summary of the following...
Introduction
• Body of the article
• Begins with a broad statement of the problem
being investigated then narrows to the
...
Methods
• Provides a detailed description of how the
study was conducted
• No conclusions drawn here
Results
• Statistic...
Discussion
• Reviews, interprets, and evaluates the results
of the study
• Non-technical language, no statistics
• Weakne...
 Advil
• “Nothing is proven more effective or
longer lasting than Advil.”
 Oral-B Toothbrush
• “You can buy a fancier to...
 The pursuit of
knowledge and its
dissemination is a
unique
characteristic of a
“profession”
 Research is the
basis for
...
 Not really a universal definition
• A structured way of answering questions,
a systematic method of inquiry
• Research i...
Uses logic that moves from
general to specific
Model for review of literature
enables the researcher to organize and
sy...
Lit Review:
• What is physical activity
• How can it effect human physiology
• What is Parkinson’s disease?
• Current tre...
Uses logic that moves from the
specific to general
Fundamental principle of scientific
method
• based upon observations ...
A way of solving problems and
acquiring knowledge that involves
both deductive and inductive
reasoning in a systematic ap...
Question Identified
Hypothesis Formed
Research Plan
Data Collected
Results Analyzed
Conclusions
New Questions
Arise
Through scientific inquiry (research),
facts are discovered
• The interpretation or explanation of these
facts is the bas...
Several research classifications have
been proposed
• Basic vs. Applied
• Quantitative vs. Qualitative
• Experimental vs....
 Purpose is to discover new or
fundamental knowledge
 Practical application is NOT a goal
• Salmonella outbreak in canta...
Purpose is to find answers to
practical problems
Diet protocol for soccer celiac disease
Recommendations for patients w...
 Positivist paradigm
• Scientific knowledge can reveal the
truth
 Traditional model of research
 Hypothesis directed
 ...
Naturalistic paradigm
multiple interpretations of reality and the goal
of researchers working within this perspective
is...
Quantitative
• Objective
• Numeric
• Statistical analysis
• Large N’s
• Structured data
collection
• Table/graphs to
disp...
The purpose of experimental research
is to investigate cause-and-effect
relationships by manipulating certain
variables t...
Tends to observe, analyze, and
describe what exists rather than
manipulating the variable under
study
Various types
Cau...
 Seeks to investigate cause-and-effect relationships similar to
experimental research
 However, researcher cannot manipu...
 Seeks to describe specific phenomena or
characteristics of a particular group of
subjects
• Answers the question “what i...
Survey
Developmental
• Longitudinal approach
• Cross-sectional approach
Case Study
Correlational
Normative
• Norm-ref...
Seeks to determine whether, and to
what extent, a relationship exists
between two or more variables
• No manipulation of ...
http://www.youtube.com/watch?v=srB
Fcb8U0p4
 Increased sales of ice cream is correlated
with increased deaths from drowning.
 The more firemen sent to the fire, the...
 Seeks to explore events and information
from the past in order to provide a better
understanding of the present with
imp...
Descriptive epidemiology –
• seeking to identify patterns or trends in
disease, injury, or death
Analytic epidemiology –...
 Cohort studies
• prospective studies – a study that begins with a
group of people (a cohort) and follows them over
time
...
 Case-control studies
• retrospective studies – a study comparing a group
who already have a condition of interest to a
g...
 A study design that randomly assigns
participants into an experimental group or
control group. The only expected differe...
• Quantitative means of reanalyzing the results from
a large number of research studies in an attempt
to synthesize findin...
1. Compile references
• There must be a substantial number
of research studies available on a
topic
• Requires means, stan...
4. Decide which studies to use
5. Do the meta-analysis
• Calculate the effect size for each
study
• Generate summary stati...
Not the ultimate answer
Does not differentiate the quality
of studies
Combines unlike studies with too
much variability...
 A very specific statement which clearly
identifies the problem being studied
• Identify the key variables
• Give some in...
“The problem of this study is to …”
“This study is concerned with …”
“This study is designed to …”
“The purpose of thi...
1.The problem was to investigate the effects of
exercise on blood lipids among college-age
females.
2.This study was desig...
 Limitations focus on potential weaknesses of
the study
 Examples include
• sampling problems
 representativeness of su...
 Possible shortcomings of the study . . .
usually cannot be controlled by the
researcher
• the researcher will, of course...
 A variable is a characteristic, trait, or
attribute of a person or thing that can be
classified or measured
• Attitude
•...
Quantitative – measured numerically
• Age
• Weight
• BMI
Qualitative – categorical in nature
• Gender
• Ethnicity
• Leve...
 A variable that is presumed to influence
another variable; the variable under
study or the one that the researcher
manip...
The variable that is expected to
change as a result of the manipulation
of the independent variable; that
which is measur...
 Independent
Variable
• The variable that is
varied or
manipulated by the
researcher
• It is the presumed
cause
 Depende...
 Effects of vitamin C on life span:
• In a study whether taking vitamin C pills daily
make you live longer, researchers w...
Effect of drug dosage on symptom
severity
• In a study of how different doses of a drug
affect the severity of symptoms, ...
 "There will be a statistically significant
difference in graduation rates of at-risk high-
school seniors who participat...
A study is conducted measuring the
effect of education on income or
wealth.
• the DV is level of income/wealth and the IV...
 You will need to understand what has
already been written about a topic before
you can ask a new question or develop a
n...
Purposes of the review will help the
researcher to:
• Gain an understanding of previous research
work
• Develop a theoret...
Once the basic question has been
identified, you need to consult the
literature to assist in fully defining the
problem
•...
Important to most research studies
Tentative explanation of the
outcome of a research problem
• The hypothesis includes ...
Research Hypothesis – An “educated
guess” or tentative proposition
regarding the possible solution or
explanation to the ...
 Null or Statistical Hypothesis - A
hypothesis of “no difference or no
relationship”
• primary use is for statistical tes...
The Research Hypothesis is
transformed into a Statistical or Null
Hypothesis (Ho)
• This is done so that statistical test...
 We want to be as sure as possible that
our theories are as correct as possible.
 We want to avoid a fluke!
• If we give...
If the null hypothesis is accepted, then the
researcher rejects the research hypothesis and
concludes there is no differe...
It is hypothesized that children taught
by teaching method A will perform
better on a reading achievement test
than child...
There will be no significant difference in
reading performance between
students taught by method A and
students taught by...
The nature of the study will determine
what type of data are required to
answer the question and the method
of collecting...
 Observation - the researcher may
watch the research participants
perform and record relevant
information about them
 Me...
 a study in which a researcher simply
observes behavior in a systematic
manner without influencing or
interfering with th...
 Researcher directly observes
research participants
 Research participants usually know
they are being observed
 Proble...
Research participants are filmed or
videotaped
Researcher views tape
Children observed while they interact in
a jungle g...
The observer participates in the
research setting with the research
participants, often spending
considerable time in the...
Scaling is the process of assigning
numbers to the various levels of a
particular concept that we wish to
measure. Thus, ...
 Rating Scale
• Selected a score from 1-10
 Semantic Differential Scale
• Clean - - - - - - - Dirty
 Rank Order Scale
•...
Individual items are judged on a single
dimension and scored on a linear scale
or continuum by selecting a numerical
or v...
How important to you is each of the issues listed below:
Extremely Extremely
Unimportant Important
1 2 3 4 5
The protectio...
Concepts No Moderate Greatest
Importance Importance Importance
Staff Discipline ___ ___ ___
Communication ___ ___ ___
Goal...
Items are ranked, usually in terms of
preference or importance, relative to
each other. This forced ranking results
in or...
Please rank the brands of beer listed below in
order of preference, with a 1 being the brand
you most prefer, 2 being your...
A very popular scaling technique
which measures the respondent’s
degree of agreement or disagreement
on an issue, opinion...
Pick a number from the scale to show how
much you agree or disagree with each
statement:
1 Strongly agree
2 Agree
3 Undeci...
 Wide variety of methods that involve
questioning the research participant
• Questionnaires
 Structured
 Unstructured
...
 Survey research - most common type of
descriptive research
 Usually self-report questionnaires pertaining
to attitudes,...
Essentially an oral questionnaire
• 24 Hour Recall
May be personal or telephone
interviews
• Structured interview
• Unst...
Essentially an interview with groups of
people
Designed to stimulate participants free
expression of feelings, beliefs, ...
What type of data is needed to answer
the research problem?
Factors to consider
• Demands on the research participant
• ...
 May include any mechanical or
electronic equipment, physical
performance task, paper-and-pencil
test or scale, as well a...
 Thoroughly review the literature
 If instrument is found, assess suitability:
• Reliability - consistency with which it...
http://www.youtube.com/watch?v=fm
EDdVEwkHc
 Nazi Experimentation in WWII
• “Medical Experiments”
 Prisoners coerced into participating & resulted in
death, disfigu...
 Nuremberg Code (1947) – first set of
guidelines
 Helsinki Declaration (1964) –
medical research
 Belmont Report (1979)...
 Arguably the most important ethical
standard
 Refers to telling research participants
about all aspects of the research...
Particular precautions must be taken
to protect the welfare of subjects that
might be considered especially
vulnerable or...
 Privacy – refers to the capacity of
individuals to control when and under
what conditions others have access to
their be...
 IRBs established by federal mandate to
assure compliance with governmental
regulations
 IRBs have authority to approve,...
 According to the U.S.
Public Health Service . . .
• “Misconduct” means
fabrication, falsification,
plagiarism, or other ...
 Researcher is responsible for his/her subjects
 Researcher is responsible for his/her own actions and
those of any rese...
Selection of Research
Participants: Sampling
Procedures
 This is considered highly important in
social and behavioral research
 Three basic questions to consider:
1. Are the re...
 Population – refers to an entire group of people or
elements having one or more common characteristics
 Target Populati...
 Random Selection
• The purpose is to enable the researcher to
generalize the results to a larger population.
Thus, the r...
 Probability Sampling
• Sampling techniques in which the probability of
selecting each participant is known
• Utilizes ra...
Probability Sampling
• Simple random sampling
• Stratified random sampling
• Systematic sampling
• Cluster sampling
Non ...
 With simple random sampling, every member of the
population has an equal probability of being
selected for the sample.
...
 An alternative to simple random sampling in which the
sampling units are selected in a series according to some
predeter...
 When members of the sample are
purposively selected because they
possess certain traits that are critical to
the study
...
 Refers to selecting research participants
on the basis of being accessible and
convenient to the researcher
 Often invo...
 Regardless of size, the crucial factor is
whether or not the sample is
representative of the population, thus
how the sa...
 Descriptive, correlational, or
experimental
• Descriptive and correlational studies typically
should have more research ...
How do you want to analyze the data?
What statistical application will be
used?
Generally N=30 is minimum needed to
meet...
Sample size is inversely related to
sampling error
• The larger the sample size, the smaller the
sampling error and the g...
 Each research participant is randomly
assigned to one of the various treatment
groups
 Each subject participates in onl...
 Subjects participate in more than one group
(treatment condition)
 In the simplest example, each research
participant w...
Single Blind Study:
• participants are unaware of whether they are
receiving the experimental or control
treatment
Doubl...
Data:
• Measures, scores, &
other info collected
in a research study.
• Refers to scores of
participants for a
variable
...
 Why is data & statistics important to
you?
◦ Useful to know data analysis techniques in
selecting the most appropriate o...
 Overall performance & characteristics
 Make comparisons between groups
• Comparing one group from another or more
 Low...
1.Select the appropriate statistical
technique
• In your procedures, you will be determining the
techniques to use. Where ...
 Statistics used to describe characteristics of
a group.
 What are the characteristics you are looking
at in your resear...
 Descriptive use of statistics is used when
measuring a trait or characteristic of a group
without an intention to genera...
 Variety of computer programs for
statistical computations; mainframe
and desktop
› SPSS
› SAS
› Statview
› Excel
 Fast,...
 The alpha level is the chance the
researcher is willing to take that the
rejection of the null hypothesis was a
mistake....
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Research ns4350fall2015

NS 4350 Module 1

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Research ns4350fall2015

  1. 1. Created by: Allison Childress MS, RDN, CSSD, LD
  2. 2. http://www.youtube.com/watch?v=fh LZ2I2MaeQ
  3. 3. 1. Title 2. Abstract 3. Introduction 4. Methods 5. Results 6. Discussion 7. References
  4. 4. Abstract • A brief summary of the entire article in approximately 120 words • Contains a concise summary of the following: (a) the article's problem under investigation or the hypothesis (b) pertinent information on the participants (c) brief review of methodology (d) statistical analyses (e) results of the study (f) implications of the study.
  5. 5. Introduction • Body of the article • Begins with a broad statement of the problem being investigated then narrows to the specific hypothesis (es) • May include the review of literature (ROL) or ROL may have its own section
  6. 6. Methods • Provides a detailed description of how the study was conducted • No conclusions drawn here Results • Statistical reporting of data • Describes what was found statistically from the data • Tables and figures
  7. 7. Discussion • Reviews, interprets, and evaluates the results of the study • Non-technical language, no statistics • Weaknesses should be reviewed • Direction or future research • Opposite of introduction References • Alphabetical order • Correct format
  8. 8.  Advil • “Nothing is proven more effective or longer lasting than Advil.”  Oral-B Toothbrush • “You can buy a fancier toothbrush. But you can’t buy a more effective one.”  Duracell Battery • “No other battery lasts longer.”  Revlon Skin Cream • “In just one week, fine dry lines and wrinkles are reduced by over 38%.”
  9. 9.  The pursuit of knowledge and its dissemination is a unique characteristic of a “profession”  Research is the basis for advancing the body of knowledge of a profession
  10. 10.  Not really a universal definition • A structured way of answering questions, a systematic method of inquiry • Research is nothing more or less than finding answers to a question in a logical, orderly, and systematic fashion  Two key components • Systematic in nature • Focuses on a question of interest  Inductive and Deductive Reasoning
  11. 11. Uses logic that moves from general to specific Model for review of literature enables the researcher to organize and synthesize available information, theorize about the problem, and deduce hypotheses to be tested by the research
  12. 12. Lit Review: • What is physical activity • How can it effect human physiology • What is Parkinson’s disease? • Current treatment options for PD • Physical activity and PD patients
  13. 13. Uses logic that moves from the specific to general Fundamental principle of scientific method • based upon observations of a small group, generalizations are made to a larger population
  14. 14. A way of solving problems and acquiring knowledge that involves both deductive and inductive reasoning in a systematic approach to obtaining information
  15. 15. Question Identified Hypothesis Formed Research Plan Data Collected Results Analyzed Conclusions New Questions Arise
  16. 16. Through scientific inquiry (research), facts are discovered • The interpretation or explanation of these facts is the basis for theory, which is a belief about how things relate to each other • Theory is not law, but could become law through additional research and experimentation • A theory establishes a cause and effect relationship between variables for the purpose of explaining and predicting phenomena (Best & Kahn, 1998)
  17. 17. Several research classifications have been proposed • Basic vs. Applied • Quantitative vs. Qualitative • Experimental vs. Non-experimental None of the various research categories are mutually exclusive
  18. 18.  Purpose is to discover new or fundamental knowledge  Practical application is NOT a goal • Salmonella outbreak in cantaloupe • Link between lack of physical activity & depression  Because there is no intervention or solution to depression we are just trying to discover a link  Usually in highly controlled laboratory settings
  19. 19. Purpose is to find answers to practical problems Diet protocol for soccer celiac disease Recommendations for patients with diabetes Creating a pesticide to reduce the outbreak of salmonella in foods Creating an exercise intervention for patients diagnosed with severe depression Practical in nature Inferences or generalizations are made to the intended population
  20. 20.  Positivist paradigm • Scientific knowledge can reveal the truth  Traditional model of research  Hypothesis directed  Based on firsthand evidence • Observed or experimental  Measured with numbers  Analyzed statistically  Examples: • Decrease in BF% after semester long Zumba course • Increase in STAR scores with mandated PE courses
  21. 21. Naturalistic paradigm multiple interpretations of reality and the goal of researchers working within this perspective is to understand how individuals construct their own reality within their social context Reliance on qualitative, non- numerical data Variety of methodologies in depth interviews direct observation Focus group and their feelings on Title IX Survey: Why do we not workout? Observing childhood social settings and its relation to fitness level
  22. 22. Quantitative • Objective • Numeric • Statistical analysis • Large N’s • Structured data collection • Table/graphs to display results Qualitative • Subjective • Non-numerical • Non-statistical analysis • Small N’s • Open ended data collection • Narrative for results
  23. 23. The purpose of experimental research is to investigate cause-and-effect relationships by manipulating certain variables to determine their effect on another variable • attempts to establish causality • manipulation of independent variable • control of extraneous variables is vital • often uses a control group • often uses randomization procedures
  24. 24. Tends to observe, analyze, and describe what exists rather than manipulating the variable under study Various types Causal-comparative Descriptive Correlational Historical
  25. 25.  Seeks to investigate cause-and-effect relationships similar to experimental research  However, researcher cannot manipulate the independent variable because it is something the subject already has • Attribute variable  Gender  Ethnicity  Medical condition  Example: • Is there a link between African Americans and sickle cell anemia • Location of residence and fitness level • Comparing diet of those diagnosed with breast cancer and those without
  26. 26.  Seeks to describe specific phenomena or characteristics of a particular group of subjects • Answers the question “what is”  Does not describe the “how come” • No manipulation of an independent variable  Wide range of methodologies • Surveys  Children’s TV time and weight • Direct measurement  BF% in female vs male track athletes • Observation  Motor development in home schooled children • Interviews  Feelings about media and physical activity popularity
  27. 27. Survey Developmental • Longitudinal approach • Cross-sectional approach Case Study Correlational Normative • Norm-reference standards Observational (a.k.a. qualitative) Causal-comparative (a.k.a. ex post facto) • Looking at past data for answers to questions
  28. 28. Seeks to determine whether, and to what extent, a relationship exists between two or more variables • No manipulation of an independent variable  Example: • Association between athletic achievement and self esteem • Correlation between mandated PE and STAAR scores • Correlation between athletic performance and sleep • Relationship among diabetics (2) and knowledge of healthy eating
  29. 29. http://www.youtube.com/watch?v=srB Fcb8U0p4
  30. 30.  Increased sales of ice cream is correlated with increased deaths from drowning.  The more firemen sent to the fire, the greater the damage.  People who wear XXXL clothing have increased incidents of heart disease.  Age is positively correlated with facial wrinkles.  Age is negatively correlated with amount of time spent Googling Justin Beiber.
  31. 31.  Seeks to explore events and information from the past in order to provide a better understanding of the present with implications for the future • Answers the question “what was”  Limited to synthesis and interpretation of data that already exists  Examples: • Researching past ticket sales and motivation in buyers to determine whether an increase in price can effect future ticket sales. • Excitement of certain events during Olympics to determine future site and future Olympic features • Past exercise interventions with those diagnosed with schizophrenia
  32. 32. Descriptive epidemiology – • seeking to identify patterns or trends in disease, injury, or death Analytic epidemiology – • seeking to determine causation of disease, injury, or death Common in public health fields
  33. 33.  Cohort studies • prospective studies – a study that begins with a group of people (a cohort) and follows them over time • Subsequent status evaluations with respect to disease or outcome are conducted to determine which initial participants risk factors are associated with it • Advantages  Subjects in cohorts can be matched which limits influence of confounding variables  Standardization of criteria /outcome is possible  Easier and cheaper than RCT
  34. 34.  Case-control studies • retrospective studies – a study comparing a group who already have a condition of interest to a group that does not  Case group – the group with the characteristic of interest (e.g., cancer)  Control group – the group without the characteristic of interest • No intervention is attempted • Advantages  Good for studying rare conditions  Less time needed to complete the study  Look at multiple risk factors simultaneously  Useful to establish and association
  35. 35.  A study design that randomly assigns participants into an experimental group or control group. The only expected difference is the outcome variable being studied  Advantages: • Good randomization will wash out population bias • Easier to blind than observational studies  Disadvantages: • Expensive – time and money • Volunteer bias • Does not reveal causation
  36. 36. • Quantitative means of reanalyzing the results from a large number of research studies in an attempt to synthesize findings • More than merely a review of related literature • In meta-analysis, each research study contributes a data point to the subsequent analysis, much like an individual participant in a descriptive or experimental research study Data as part of the entire analysis = individual participants data as part of the entire research study
  37. 37. 1. Compile references • There must be a substantial number of research studies available on a topic • Requires means, standard deviations, correlations, etc. published 2. Determine inclusive criteria • E.g., published in last 10 years or N > 30 3. Review each study • Record information needed to calculate ES from each study
  38. 38. 4. Decide which studies to use 5. Do the meta-analysis • Calculate the effect size for each study • Generate summary statistics for effect sizes • Interpret results 6. Report the results
  39. 39. Not the ultimate answer Does not differentiate the quality of studies Combines unlike studies with too much variability (i.e., mixing apples and oranges)
  40. 40.  A very specific statement which clearly identifies the problem being studied • Identify the key variables • Give some information about the scope of the study • Formulation of problem statement takes place after an initial review of related literature and the distillation process • This is the purpose of the research
  41. 41. “The problem of this study is to …” “This study is concerned with …” “This study is designed to …” “The purpose of this investigation is to …”
  42. 42. 1.The problem was to investigate the effects of exercise on blood lipids among college-age females. 2.This study was designed to determine the relationship between stability performance and physical growth characteristics of preschool children. 3.The present study was designed to identify those characteristics which differentiate between students who binge drink and those that do not. 4.The problem of the study was to determine if there was a relationship between self-efficacy and self- reported alcohol usage among middle-aged adult females.
  43. 43.  Limitations focus on potential weaknesses of the study  Examples include • sampling problems  representativeness of subjects: low # of subjects, subjects lying • uncontrolled factors and extraneous variables  Weather, suspended funding, etc. • faulty research design and techniques  Length of study not long enough, participants adapted to study protocol • reliability and validity of measuring instruments  Blood work sampling can have low validity 1. The accuracy of the results was dependent on the participants adhering to the intervention protocols (i.e., consuming the proper antioxidants and the correct amount each day). 2. The participant’s truthfulness on the compliance check sheet.
  44. 44.  Possible shortcomings of the study . . . usually cannot be controlled by the researcher • the researcher will, of course, try to eliminate extremely serious weaknesses before the study is commenced  May be a result of assumptions not being met • Assume subjects follow protocol  No study is perfect; the researcher recognizes the weaknesses
  45. 45.  A variable is a characteristic, trait, or attribute of a person or thing that can be classified or measured • Attitude • Gender • Heart rate • Hair color  Exclusion and Inclusion criteria for choosing participants • Excluded-smokers, previous injury, male, etc. • Included-ages 6-18, currently on BC, healthy BMI, etc.
  46. 46. Quantitative – measured numerically • Age • Weight • BMI Qualitative – categorical in nature • Gender • Ethnicity • Level of Education
  47. 47.  A variable that is presumed to influence another variable; the variable under study or the one that the researcher manipulates  Two types • Active – variable is actually manipulated  Exercise Intensity  Diet • Attribute- cannot be manipulated because it is preexisting trait; sometimes called a “categorical” variable (Research type: casual comparative)  Race  Gender
  48. 48. The variable that is expected to change as a result of the manipulation of the independent variable; that which is measured in a study
  49. 49.  Independent Variable • The variable that is varied or manipulated by the researcher • It is the presumed cause  Dependent Variable • The response that is measured • It is the presumed effect • Depends on the outcome of the independent variable
  50. 50.  Effects of vitamin C on life span: • In a study whether taking vitamin C pills daily make you live longer, researchers will dictate the vitamin C intake of a group of people over time. One part of the group will be given vitamin C pills daily. The other part of the group will be given a placebo pill. Nobody in the group knows which part they are in. The researchers will check the life span of the people in both groups. • Here, the dependent variable is the life span and the independent variable is the vitamin C. http://en.wikipedia.org/wiki/Dependent_and_independent_variables
  51. 51. Effect of drug dosage on symptom severity • In a study of how different doses of a drug affect the severity of symptoms, a researcher could compare the frequency and intensity of symptoms when different doses are administered. • Here the independent variable is the dose and the dependent variable is the frequency/intensity of symptoms. http://en.wikipedia.org/wiki/Dependent_and_independent_variables
  52. 52.  "There will be a statistically significant difference in graduation rates of at-risk high- school seniors who participate in an intensive study program as opposed to at- risk high-school seniors who do not participate in the intensive study program.“  IV: Participation in intensive study program. DV: Graduation rates.
  53. 53. A study is conducted measuring the effect of education on income or wealth. • the DV is level of income/wealth and the IV is the education level of the individual.
  54. 54.  You will need to understand what has already been written about a topic before you can ask a new question or develop a new way of answering an old question • Past literature can help pinpoint exactly what you want to research and your statement of purpose • Past literature can help you to develop a successful research proposal • Past literature used in your review can be similar, or have differences that allow you to think outside the box • Past literature can help to determine if there is a gap in the specific topic or method you wish to use
  55. 55. Purposes of the review will help the researcher to: • Gain an understanding of previous research work • Develop a theoretical understanding of the topic • Distill the question into a specific problem • Develop a research plan (methods)  Research approach and design  Procedures and instrumentation • Identify a question
  56. 56. Once the basic question has been identified, you need to consult the literature to assist in fully defining the problem • Conceptual literature • Related research Serves as the basis for hypothesis development
  57. 57. Important to most research studies Tentative explanation of the outcome of a research problem • The hypothesis includes a decrease in fat percentage and depression during an exercise/nutrition education program.
  58. 58. Research Hypothesis – An “educated guess” or tentative proposition regarding the possible solution or explanation to the problem being studied • based on theory or previous research THERE IS A SIGNIFICANT DIFFERENCE IN ANXIETY LEVELS OF CHILDREN WITH HIGH IQ AND THOSE WITH LOW IQ
  59. 59.  Null or Statistical Hypothesis - A hypothesis of “no difference or no relationship” • primary use is for statistical testing • hypothesis which says the independent variable has no effect on the dependent variable • does not necessarily reflect the researcher’s expectations • Believe this until proven otherwise THERE IS NO SIGNIFICANT DIFFERENCE IN ANXIETY LEVELS OF CHILDREN WITH HIGH IQ AND THOSE WITH LOW IQ
  60. 60. The Research Hypothesis is transformed into a Statistical or Null Hypothesis (Ho) • This is done so that statistical tests can be employed that will determine whether the findings are statistically significant or can be attributed to chance • The results of the statistical test will enable the researcher to accept or reject the null hypothesis
  61. 61.  We want to be as sure as possible that our theories are as correct as possible.  We want to avoid a fluke! • If we give out a new drug and by chance people get better (when the researcher knows it is inactive), then it is a fluke  So, statistical testing tests the probability that your null hypothesis is true or not.
  62. 62. If the null hypothesis is accepted, then the researcher rejects the research hypothesis and concludes there is no difference between the groups If the null hypothesis is rejected, then the research hypothesis is affirmed and the researcher concludes there is a significant difference between the groups
  63. 63. It is hypothesized that children taught by teaching method A will perform better on a reading achievement test than children taught by method B
  64. 64. There will be no significant difference in reading performance between students taught by method A and students taught by method B or Teaching method has no effect on the reading performance of students
  65. 65. The nature of the study will determine what type of data are required to answer the question and the method of collecting these data Multiple techniques may be used in a single study
  66. 66.  Observation - the researcher may watch the research participants perform and record relevant information about them  Measurement - the researcher may test the research participants or apply a device to measure certain qualities  Questioning - the researcher may ask the research participants questions to obtain information
  67. 67.  a study in which a researcher simply observes behavior in a systematic manner without influencing or interfering with the behavior • Direct observation • Indirect observation • Participant observation Example: observe patient’s chewing during a meal with and without dentures
  68. 68.  Researcher directly observes research participants  Research participants usually know they are being observed  Problem?: • Researcher’s presence might change the way the research participants act Observing subjects as they run a mile; many say the pressure can increase/decrease motivation and performance
  69. 69. Research participants are filmed or videotaped Researcher views tape Children observed while they interact in a jungle gym alone, with same gender, with group of children, with adults.
  70. 70. The observer participates in the research setting with the research participants, often spending considerable time in the natural setting developing field notes Qualitative research methodology Observe the daily physical activity in a specific population and taking field notes
  71. 71. Scaling is the process of assigning numbers to the various levels of a particular concept that we wish to measure. Thus, a scale provides an indirect measure of the concept of interest • Rating of perceived exertion (RPE): 6-20 Scales can be used to obtain information on almost any topic, object, or subject. • Attitude, opinion, behavior, performance, and perception are frequently measured by some type of scale
  72. 72.  Rating Scale • Selected a score from 1-10  Semantic Differential Scale • Clean - - - - - - - Dirty  Rank Order Scale • Rank the products in order of perceived quality  Likert Scale • Strongly agree-agree-neutral-disagree, strongly disagree
  73. 73. Individual items are judged on a single dimension and scored on a linear scale or continuum by selecting a numerical or verbal point on the scale that corresponds to their impression of the item
  74. 74. How important to you is each of the issues listed below: Extremely Extremely Unimportant Important 1 2 3 4 5 The protection of endangered species of animals ____ The improvement of the quality of the air ____ The provision of social services to those in need ____
  75. 75. Concepts No Moderate Greatest Importance Importance Importance Staff Discipline ___ ___ ___ Communication ___ ___ ___ Goal Setting ___ ___ ___ Public Relations ___ ___ ___ Computer Use ___ ___ ___ Administrative Concept Scale
  76. 76. Items are ranked, usually in terms of preference or importance, relative to each other. This forced ranking results in ordinal scores, thus limiting the statistical treatment of the scores  the intervals between score points are not always equal The number of items to be ranked should be less than 10, to avoid making the task too difficult
  77. 77. Please rank the brands of beer listed below in order of preference, with a 1 being the brand you most prefer, 2 being your second choice, and so forth. ____ Budweiser ____ Coors ____ Miller ____ Corona
  78. 78. A very popular scaling technique which measures the respondent’s degree of agreement or disagreement on an issue, opinion, or particular belief The continuum of response typically runs from SA , A, U, D, to SD Responses to a Likert scale can be considered to be interval level scores, thus allowing scores to be summed and treated statistically
  79. 79. Pick a number from the scale to show how much you agree or disagree with each statement: 1 Strongly agree 2 Agree 3 Undecided 4 Disagree 5 Strongly disagree College athletes should be paid ____ A woman’s place is in the home ____ Participating in sports is all about winning ____
  80. 80.  Wide variety of methods that involve questioning the research participant • Questionnaires  Structured  Unstructured  Checklist • Interviews
  81. 81.  Survey research - most common type of descriptive research  Usually self-report questionnaires pertaining to attitudes, behaviors, practices, likes, dislikes, etc. • Food Frequency Questionnaire (FFQ)  May be mailed, distributed by the researcher or completed online  Many formats • Have you completed a survey in the past year?
  82. 82. Essentially an oral questionnaire • 24 Hour Recall May be personal or telephone interviews • Structured interview • Unstructured interview
  83. 83. Essentially an interview with groups of people Designed to stimulate participants free expression of feelings, beliefs, etc. Requires a skilled facilitator to guide discussion
  84. 84. What type of data is needed to answer the research problem? Factors to consider • Demands on the research participant • Costs in terms of money, energy, and time • Ability of the researcher to handle the selected technique, including the data analysis
  85. 85.  May include any mechanical or electronic equipment, physical performance task, paper-and-pencil test or scale, as well as a questionnaire designed to collect data on the variable of interest  Researcher’s choice of instrument involves deciding if • one already exists that can be used as is • if one exists but needs to be revised • if one needs to be developed
  86. 86.  Thoroughly review the literature  If instrument is found, assess suitability: • Reliability - consistency with which it measures • Validity - measures what it is suppose to measure  Reliability and validity of an instrument are often specific to the age, gender, characteristics of subjects on which it is used  Without acceptable reliability and validity, the data are of no use in answering the research question • Objective - free from scorer bias • Appropriateness to current study • Ease of administration and scoring
  87. 87. http://www.youtube.com/watch?v=fm EDdVEwkHc
  88. 88.  Nazi Experimentation in WWII • “Medical Experiments”  Prisoners coerced into participating & resulted in death, disfigurement & disability  Bone, muscle, nerve transplantation  Head/hammer injury experiment  Hypothermia studies  Mustard gas exposure • Nuremberg War Crime Trials • Nuremberg Code – basic principles to govern research involving human subjects  Tuskegee Syphilis Study • Public Health Service project related to untreated syphilis • Highlights deception and informed consent  Human radiation experiments
  89. 89.  Nuremberg Code (1947) – first set of guidelines  Helsinki Declaration (1964) – medical research  Belmont Report (1979) – fundamental document for current federal regulations in US  Common Rule (1991) – 45 C.F.R. 46 • Federal rules that govern research involving human participants in the US  Institutional Review Boards (IRB)
  90. 90.  Arguably the most important ethical standard  Refers to telling research participants about all aspects of the research that might reasonably influence their decision to participate  Four important elements 1. Subjects are fully aware of nature and purpose of research project 2. Consent is voluntarily given 3. Person has legal capacity to give consent 4. Responsibility for obtaining consent rests with researcher
  91. 91. Particular precautions must be taken to protect the welfare of subjects that might be considered especially vulnerable or at risk for some reason The following types of subjects might be considered to be vulnerable: children, handicapped, cardiac rehab patients, welfare recipients, prisoners, pregnant women, patients in a mental hospital, etc.
  92. 92.  Privacy – refers to the capacity of individuals to control when and under what conditions others have access to their behaviors, beliefs, and values • Participants stance  Confidentiality – refers to treating subject information or responses in a manner so that it is not linked to any specific individual who participated in a study • Researchers responsibilities  Normally addressed through informed consent
  93. 93.  IRBs established by federal mandate to assure compliance with governmental regulations  IRBs have authority to approve, require modifications, or disapprove research  IRB approval required before any aspect of the research involving human subjects may commence
  94. 94.  According to the U.S. Public Health Service . . . • “Misconduct” means fabrication, falsification, plagiarism, or other practices that seriously deviate from those that are commonly accepted within the scientific community for proposing, conducting, or reporting research
  95. 95.  Researcher is responsible for his/her subjects  Researcher is responsible for his/her own actions and those of any research aides  Subjects must provide informed consent  Researcher protects subjects from harm, danger, and discomfort  Maintain anonymity and confidentiality  Subjects should not be coerced  Researcher has responsibility after the investigation is complete to safeguard subject data  Honest disclosure of results
  96. 96. Selection of Research Participants: Sampling Procedures
  97. 97.  This is considered highly important in social and behavioral research  Three basic questions to consider: 1. Are the research participants appropriate for the research question? 2. Are the research participants representative of the population of interest? 3. How many research participants should be used?
  98. 98.  Population – refers to an entire group of people or elements having one or more common characteristics  Target Population – the group that is the focus of your research  Accessible Population – members of the population that you can reach  Sample – a small subgroup of a population of interest thought to be representative of that population • Sampling Unit – one member of your population  Sampling – the process of selecting a subgroup or sample of the population
  99. 99.  Random Selection • The purpose is to enable the researcher to generalize the results to a larger population. Thus, the researcher is concerned about the “representativeness” of the subjects in the sample  Random Assignment • The purpose is to enable the researcher to assume that groups are “equivalent” at the beginning of the study. This adds control to a study; it has nothing to do with the selection of the sample
  100. 100.  Probability Sampling • Sampling techniques in which the probability of selecting each participant is known • Utilizes random processes, but does not guarantee the sample is representative of population • Estimates of sampling error are possible  Non Probability Sampling • Samples are not selected at random • Difficult to claim sample is representative of population • You can’t estimate the sampling error • Intact groups, volunteers
  101. 101. Probability Sampling • Simple random sampling • Stratified random sampling • Systematic sampling • Cluster sampling Non Probability Sampling • Purposive sampling • Convenience sampling
  102. 102.  With simple random sampling, every member of the population has an equal probability of being selected for the sample.  Also, the selection of one member of the population does not affect the chances of any other member being chosen (equal and independent)  Example: The population might be all hospitals in the U.S. that perform heart bypass surgery.  Usual procedure: • Fishbowl technique • Table of random numbers • Computer generated sampling
  103. 103.  An alternative to simple random sampling in which the sampling units are selected in a series according to some predetermined sequence. The origin of the sequence should be controlled by chance  The researcher will choose 1/kth of the sampling frame with k being any constant. The first sampling unit is randomly selected by the investigator. Thereafter, every kth unit in the sampling frame is chosen • Put names in alphabetical order and choose every 5th person  Simple random sampling is to be preferred, but systematic sampling is a practical and useful approximation to random sampling that is easier to perform
  104. 104.  When members of the sample are purposively selected because they possess certain traits that are critical to the study  Example: Selecting celiac patients for an oat sensitivity study
  105. 105.  Refers to selecting research participants on the basis of being accessible and convenient to the researcher  Often involves use of volunteers  Example: Using fellow graduate students as research participants
  106. 106.  Regardless of size, the crucial factor is whether or not the sample is representative of the population, thus how the sample is selected  Points to consider regarding sample size: • Nature of the study • Statistical considerations • Variability of population • Number of treatment groups • Practical factors
  107. 107.  Descriptive, correlational, or experimental • Descriptive and correlational studies typically should have more research participants • Experimental studies often employ fewer research participants
  108. 108. How do you want to analyze the data? What statistical application will be used? Generally N=30 is minimum needed to meet assumptions of many statistical procedures
  109. 109. Sample size is inversely related to sampling error • The larger the sample size, the smaller the sampling error and the greater likelihood that the sample is representative of the population Little variability – small sample will suffice High variability – sample size will be larger
  110. 110.  Each research participant is randomly assigned to one of the various treatment groups  Each subject participates in only one group  Avoids carry-over effect due to cross over  Test the effects of caffeine on cognitive function: • one group of subject's math ability might be tested after they consume caffeine • And another group of subject’s math ability tested after they consume a placebo
  111. 111.  Subjects participate in more than one group (treatment condition)  In the simplest example, each research participant would be assigned to each level of the independent variable and then is measured after receiving the treatment  Counterbalancing is often used to control for possible order effect  Wash out times may help avoid carry-over effect  Cross-over Design • to test the effects of caffeine on cognitive function, a subject's math ability might be tested once after they consume caffeine and after they receive a placebo
  112. 112. Single Blind Study: • participants are unaware of whether they are receiving the experimental or control treatment Double Blind Study • participants and researcher are unaware of the groups and who is receiving the experimental or control treatment
  113. 113. Data: • Measures, scores, & other info collected in a research study. • Refers to scores of participants for a variable  Change in BMI when a reduced calorie diet is followed
  114. 114.  Why is data & statistics important to you? ◦ Useful to know data analysis techniques in selecting the most appropriate one for your own research ◦ Useful when reading your Literature Review articles
  115. 115.  Overall performance & characteristics  Make comparisons between groups • Comparing one group from another or more  Low Fat vs Low Carb: Compare weight loss  One group will prevail from the others  Make comparisons within groups • Comparing data gathered from one group  Mediterranean diet intervention: Compare subjects within this group on lower CV risk factors and weight  To see the percentage of change from this one group
  116. 116. 1.Select the appropriate statistical technique • In your procedures, you will be determining the techniques to use. Where can you get ideas? 2.Apply the technique • Gather your numbers or results and input into a data analysis program such as SPSS  Using a computer program helps to reduce time and mistakes from human error (plus, I suck at math!) 3.Interpret the result
  117. 117.  Statistics used to describe characteristics of a group.  What are the characteristics you are looking at in your research? • Weight loss • Recovery rate after surgery • Biochemical Improvement • Performance after various sleep time • Mood after exercising
  118. 118.  Descriptive use of statistics is used when measuring a trait or characteristic of a group without an intention to generalize that statistic beyond that group. • Mean: Average • Median: Midpoint • Mode: Most frequent • Standard deviation • Range of scores  Inferential use of statistics occurs when one makes generalizations or inferences from a smaller group to a larger group.
  119. 119.  Variety of computer programs for statistical computations; mainframe and desktop › SPSS › SAS › Statview › Excel  Fast, easy to use, widely available
  120. 120.  The alpha level is the chance the researcher is willing to take that the rejection of the null hypothesis was a mistake.  It is typically reported as a “p value”, such as “the results were significant at p < .05”, or p < .01, or p < .001

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