Science Nutritional Discussion March 7: Study Worksheet
Define epidemiological research:Match the four types of epidemiological research
Epidemiological study: Observe subjects behavior and collect
data but do not assign a treatment or exposure
1. Compares those with disease (or other outcome) to those
without. For example, comparing obese men to normal weight
men (who act as the controls) to see how their diets differed in
fat consumption.
A. Ecological
Case Control Study
2. Examines patterns across a large area such as a city, state or
nation. For example, Japan has high rates of fish consumption
and low rates of CHD. Beware of the ecological fallacy - what
is true for the group may not be true for the individual.
B. Cohort
Ecological
3. A snapshot in time involve data collected at a defined time.
Surveys are an example of a cross- sectional study. They are
C. Case-Control
often used to assess the prevalence of acute or chronic
conditions, or to answer questions about the causes of disease or
the results of medical intervention.
Cross-sectional
4. Compares exposed to unexposed (or multiple exposures) to
see who develops disease (or outcome of interest). For example,
following vegetarians and non-vegetarians to see who gains
more weight over time
D. Cross- sectional
Cohort study
What is a control group: standard that is compared to the test group to test products
effectiveness
Ie. Comparing placebo group to real group
Define experimental research and list what experiments typically consist of.
1. Testable hypothesis
2. Test group and control group: Standard that is compared to the test group to test
the products effectiveness
Ie. Drug study: drug v. placebo
3. Appropriate experimental design
4. Quantifiable data: specific numbers to evaluate whether proved/disproved
hypothesis
When reading a research paper, what information can you expect to find in the following
sections?
Abstract: brief (information) background into topic, describe major findings
and relevance of findings
Introduction: more background information to show why research is important
and relevant to the field
Materials and Methods: List materials used in the experiment and how the
experiment was carried out (lab manual)
Results: Lists data obtained from experiment, generally graphs, charts and
tables: generally no explanation of results/why theyre relevant, just raw data
Discussion: Interpret results of experiments and tie data/results back to
hypothesis. Also list limitations of the experiment. Relate your experimental findings to
other findings in that field (reference other research papers: conflicting/confirming)
References/Acknowledgements: List papers/other references used (kind of like
bibliography)
In order to understand a research paper, which questions should you address?
1.What topics are going to be addressed in paper
2.What are the main conclusions of the paper
3. What evidence supports these conclusionsimportant evidence actually supporting
conclusions?
4. Why are the conclusions important/significance of the study: any new discoveries,
confirmation of old studies, conflicting
*Remember: correlation does not equal causation. What does this mean? (just because
research paper proves hypothesis, does not necessarily mean hypothesis is proving
causation)
List three factors you should consider when evaluating the quality of research.
1. Did the experiment use appropriate subjects and controls (good experimental
designcorrect population)
Invivo: inside organism experiments
Invitro: test tubes does not show how it interacts within the body
2. What methods were used and what were the limitations of those methods:
ie. Sample size and duration of the study (measures validity)
3. Any possible conflict of interest: many manufacturers hire own scientists to
perform studiescan lead to experimental bias