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Eur Psychiatry. 2018 Mar;49:69-77. doi: 10.1016/j.eurpsy.2017.12.025. Epub 2018 Feb 3.
Efficacy of non-invasive brain stimulation on the symptom dimensions of schizophrenia: A meta-analysis of randomized controlled trials.
Their stated objective was:
To quantify the efficacy of double-blind randomized controlled trials (RCT) of tDCS and rTMS for the positive and negative symptoms of schizophrenia and identify significant moderators relating to patient-related features and stimulation parameters.