1.9 Flashcards
Why is it difficult to study nutrition?
- People change diet constantly
- Can’t force diets on people
- Can’t know for certain what people eat
- Factors beyond nutrition
- Can’t establish causation
What are the steps of the scientific method in this course?
- Define problem
- Observe on existing data
- Create hypothesis
- Develop study methods
- Experiment (take detailed results)
- Analyze data
- Draw conclusions (reject/accept hypothesis)
Experimental studies (or randomized control trials) usually involves what 2 groups?
Experimental and Control group. Only one variable is changed between the two groups so we can determine that the variable caused the change.
Most nutrition studies are ___________ studies
epidemiological
What is an epidemiological study?
A population-based study based on looking at population trends without manipulating variables
What is an example of an epidemiological study?
Do Japanese people who eat a lot of fish have a lower risk of cardiovascular disease than Americans?
Why should we always be skeptical of epidemiological studies?
There could be other factors not taken into account that affect the data (genetics, physical exercise between groups, might eat other things not reported, etc).
Associations does not equal causation, basically.
There is no ideal method for determining what people eat.
What is anecdotal evidence? Why is it bad?
Personal stories drawn from direct or indirect casual experiences.
Not scientific or peer-reviewed.
Where can you found credible nutritional studies?
Pubmed, Google Scholar and libraries.
What are systematic reviews?
Reviews that aggregate many articles and provide a general message.
What is the VETO strategy?
Valuable - does it add to an evidence base that’s already there?
Evidence-based - proper scientific method employed?
Trustworthy - what’s the source?
Opinion - does it seem like it’s just a personal opinion?
What is a blind and double-blind study?
Blind - Participants don’t know which group they are in.
Double-blind - Scientists don’t know which group they are studying either
Both reduces bias and psychological effects.
What is a prospective epidemiological design?
An experiment where a large, similar group is followed forward through time.
What is a journal’s impact factor?
A way of determining importance and rank based on how many times it has been cited by others
