Placebo effect

What are placebo effects?

Placebo effects in pharmaceutical trials vary widely, with response rates varying from 20% to 70%. The placebo response can include improvement in symptoms and even adverse reactions that have been associated with the drug being tested. Placebo effects can substantially influence conclusions about the efficacy of medications as they minimise any differences in response.

What is the evidence on placebo effects in trial for PTSD?

Moderate to high quality evidence found large improvements from baseline to endpoint with both placebo and antidepressants, with a small effect of greater improvement with antidepressants.

August 2021

Image: ©Dariusz T. Oczkowicz-

Last updated at: 5:19 am, 28th July 2021
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Fact Sheet Technical Commentary

NeuRA Libraries

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