Why does there have to be a plecebo/control group in a drug test?
In: Biology
Humans are very complex, and one is a lot like another, but also very different from another. Does blood pressure medicine A lower my blood pressure the same amount it lowers yours?
And outcome measures can have a level of subjectiveness to them; weight is fairly objective, pain is not. And the observers/recorders often have conscious and unconscious biases that affect their reporting.
People who meet certain criteria enter into a study, and are randomized to the treatment group or the control group. They are randomized to increase the likelihood that other confounding variables that we don’t know about or didn’t consider in our inclusion criteria are equally balanced between the two groups. Ideally, neither the participants nor the observers know which group you are in, reducing the biases that can come from “I’m taking the active treatment” or “this person is taking placebo.” In the perfect study, the only variable that would be different in the two groups would the substance being tested. This increases the likelihood that any observed differences in the groups reflects an actual treatment effect rather than some other confounding variable(s).
The placebo effect (improvement in condition after taking a placebo) is as high as 20%; the human mind can be a powerful thing.
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