Placebos Are Getting More Effective. Drugmakers Are Desperate to Know Why.
Two comprehensive analyses of antidepressant trials have uncovered a dramatic increase in placebo response since the 1980s. One estimated that the so-called effect size (a measure of statistical significance) in placebo groups had nearly doubled over that time.
It's not that the old meds are getting weaker, drug developers say. It's as if the placebo effect is somehow getting stronger.
