1. Nutrition Research Overview
From Research Study to the Media
Secondary & Primary Sources
Explore How Research is Conveyed in the News
Scientific Method
7 Steps
2 Main Types of Research Design
Observational
Experimental
One Study Doesn’t Prove a Finding
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2. Sources of Scientific Information
Secondary Sources & Media:
Resource that informs us of scientific research
Scientific news from websites, blogs, TV, magazines, friends…
Primary Source:
Original Research
Best research is published in scientific (peer-reviewed) journals
As scientific research gets interpreted by others, less detail is provided and more opinion and sensationalism is introduced
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3. Journalists who interpret scientific findings…
Journalists who interpret scientific findings….some qualified and many not qualified
Important to know if the information you receive is accurate.

4. News Headline: Lack of Vitamin D Makes Kids Fat
Research at U of M (published in JCN) followed 479 youngsters over 30 months.
“We found that the kids with the lowest Vitamin D levels…tended to gain weight faster than the kids with higher levels.”
“Our findings suggest that low vitamin D status may put children at risk of obesity.”

5. Scientific Method
Process all scientists follow to gain scientific knowledge.
There are 7 steps in the scientific method
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6. Scientific Steps: Question or observation
Purpose of study or hypothesis (a testable statement)
Design the study:
Develop a plan to test the hypothesis
Choose design type: observational or experimental
Implement the research design
Collect & analyze data
Interpret results
State results or accept/reject hypothesis
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7. Scientific Step 3. Design
Determine if finding correlation or cause/effect
Correlation (Association): When a change in one variable is RELATED to a change in another variable.
Cause and Effect: When a change in one variable CAUSES a change in another variable
2 Main Types of Research Design
Observational
Prospective
Experimental
Clinical Trial
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8. Observational Study
Scientists do NOT ask people to change their behaviors or undergo any treatment.
Data collected by recording observations & data
Minimal risk to participants
Can suggest association, NOT cause & effect
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9. Prospective Study Prospective Study – type of observational study
Follow a group of healthy people with different levels of exposure and observe effects on health or disease.
Risk factor: a condition or behavior that increase the likelihood that a particular disease or condition will develop.
Framingham Study
Began in 1948 to determine relationship between diet, lifestyle and heart disease.
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10. Prospective study
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11. Experimental Study Researchers intervene Random assignment
Participants divided into treatment or control (no treatment) group
Can suggest cause & effect
Random assignment
Participants have equal chance to be in treatment or control group
Factors that may affect the outcome are distributed equally among the two groups
Single-blind:
Participants in control group are given a placebo
The participants do not know who receives treatment but researchers do know
Opportunity for bias
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12. Experimental Study, cont.
Double Blind
Neither the researcher nor participants knows whether treatment or placebo is given
A member of research team holds code for group assignments and does not participate in data collection
If significant difference found between treatment & control group treatment caused the effect
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13. Headline: Lack of Vitamin D Makes Kids Fat
Research at U of M (published in Journal of Clinical Nutrition) followed 479 youngsters over 30 months.
“We found that the kids with the lowest Vitamin D levels…tended to gain weight faster than the kids with higher levels.”
“Our findings suggest that low vitamin D status may put children at risk of obesity.”

14. Ice Cream & Drowning
Studies have shown that in the U.S. drowning rates are highest in areas with high ice cream sales.
The higher the ice cream sales…the more likely people are going to drown.

15. Headline: Ice Cream Makes you Drown
Does ice cream make you drown…cause drowning?
If you eat ice cream, are you more likely to drown?
What is the connection between ice cream & drowning?

16. Water
Ice cream sales tend to be high near water (pools and beaches) – people more likely to drown near water.
The connection is between water & drowning…NOTHING to do with ice cream.
Headline: ICE CREAM MAKES YOU DROWN is incorrect and misleading

17. Vitamin D & Weight Gain
The research found there is an association (link) between kids with low Vitamin D & weight gain.
The weight gain may or may not be due to low Vitamin D levels.
More studies are needed. One credible (peer-reviewed) study isn’t fact.

18. Scientific Steps: Question or Observation
Purpose or Hypothesis (testable statement)
Design:
Develop a plan to test the hypothesis
2 main types: observational & experimental
Implement the research design
Collect & analyze data
Interpret results
State results or accept/reject hypothesis
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19. Scientific Steps: 4. Implement, 5. Analyze, 6. Interpretation
Implement: Data collected on each participant
Analyze data to see if the difference between “Group A & Group B” is “statistically significant”
Statistical Significance: The difference between groups did not happen by chance.
Interpret: What new knowledge was gained by this research?
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20. Scientific Step 7. State results & accept/reject hypothesis
If there is a “statistically significant” difference, then results show a correlation or cause & effect
Findings reviewed by board of scientists. If conclusions are accurate, study results are published in a peer-reviewed scientific journal.
One study doesn‘t prove a finding. Findings need to be repeated in several kinds of studies, by different researchers.
News media may report new findings before confirmed by other research.
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21. Observational vs Experimental
Type of study
Ethical?
Results
Random Assign?
Dbl Blind?
Observational
Experimental
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