CNN —When you’re trying to address mental health symptoms, simply the belief that you can be helped may be an important factor. Symptoms of nine mental health disorders substantially improved under placebo treatment, according to a new review of 90 randomized controlled trials — known as a meta-analysis — totaling 9,985 adult participants largely in their 30s and 40s. “This is the most comprehensive study of placebo effects in psychiatry.”The results are also important for patient treatment, Bschor said. But for disorders that didn’t see as much improvement with placebos — such as OCD or schizophrenia, which is a psychotic disorder — medication may be more necessary. Improvement in absence of medicationThat mental health symptoms improved with placebo treatment may be due to a few potential influences, experts said.

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Persons: Tom Bschor, Jonathan Alpert, Dorothy, Marty Silverman, Alpert, wasn’t, Bschor, ” Bschor, ”, Richard Keefe, Keefe, Felipe Barreto Schuch, ” Schuch wasn’t, “, ” Alpert, you’ve Organizations: CNN, Psychiatry, University Hospital Dresden, Albert Einstein College of Medicine, Duke University Medical Center, Brazil’s Federal University of Santa Locations: Germany, New York City, North Carolina, Brazil’s Federal University of Santa Maria