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D035843:Biomedical Research / Q000639:trends; D002986:Clinical Trials as Topic / Q000592:standards*; D016208:Databases, Factual / Q000592:standards*; D016021:Epidemiologic Studies; D006801:Humans; D011570:Psychiatry / Q000639:trends; D012042:Registries / Q000706:statistics & numerical data*