Chapter 2
In vitro
"Test tube" experimenting on parts derived from living organism, such as cells.
Placebo
A fake treatment, such as a sham pill, injection, or medical procedure.
Experiment
A systematic way of testing a hypothesis.
Control group
Does not receive treatment; human subjects may receive a placebo.
Case-control study
Individuals who have a health condition are compared with individuals with similar characteristics who do not have the condition.
Experimental epidemiological studies
Obtain information about health conditions that may have resulted from specific dietary practices.
Variable
Personal characteristic or other factor that changes and can influence an outcome.
Hypothesis
Possible explanation about an observation that guides scientific research.
Treatment group
Receives treatment.
Anecdote
Reports of personal experiences.
Cohort study
Study that measures variables in a group of people over time.
In vivo
Testing on whole living organisms, such as lab rodents.
What Is the Placebo Effect?
The placebo effect occurs when a person reports a positive (or negative) reaction to a treatment even though he or she received the placebo.
Epidemiology
The study of occurrence, distribution, and causes of health problems in populations.