Premorbid IQ in Schizophrenia: A Meta-Analytic Review
American Journal of PsychiatryPublished 15 April 2008
Kristen A. Woodberry, Anthony J. Giuliano, Larry J. Seidman
Citations558
SJR quartileQ1
SJR score5.27
SNIP3.68
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TL;DR
Overall, schizophrenia samples demonstrated a reliable, medium-sized impairment in premorbid IQ, and all studies with pre- and post-onset testing within the same sample suggested that a significant decline in the IQ of individuals with schizophrenia, relative to comparison subjects, was associated with the onset of frank psychosis.
Abstract
Years before the onset of psychotic symptoms, individuals with schizophrenia, as a group, demonstrate mean IQ scores approximately one-half of a standard deviation below that of healthy comparison subjects.
Keywords
Medicine
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