What is the difference between a clinical trial and an observational study?
In a clinical trial, researchers are testing a new treatment–exercise, vitamins, drugs, or other forms of therapy–and comparing it to standard treatment, (the usual care recommended by doctors in that particular situation). Clinical trials are studies that evaluate the effectiveness of new interventions. There are at least two groups of people in the study, one group receiving the new therapy and one group receiving standard therapy. Sometimes the group receiving standard therapy gets what is called a placebo–a dummy pill, or treatment, that looks identical–so that no one can tell which group they are in. When neither the researchers nor the participants know which group is which, it is called a double masked or double blind study. An observational study means the investigators are doing just that–observing. They are not giving participants any treatment, but only checking their health and perhaps monitoring special items, like a woman’s cholesterol level or blood pressure, for ex
