Prevalence of Schizophrenia Spectrum Disorders in Average-IQ Adults with Autism Spectrum Disorders: A Meta-analysis
Since their separation as independent diagnostics, autism spectrum disorders (ASD) and schizophrenia spectrum disorders (SSD) have been conceptualized as mutually exclusive disorders. Similarities between both disorders can lead to misdiagnosis, especially when it comes to average-IQ adults who were not identified during childhood. The aim of this review was to examine the occurrence of SSD in average-IQ adults with ASD. Electronic and manual searches identified a total of 278 references, of which 10 were included in a meta-analysis. The pooled prevalence of SSD in the total ASD sample was close to 6%, pointing to a high co-occurrence of the two conditions. Further research is needed to determine the factors that predispose members of this population to the emergence of psychotic disorders.
KeywordsAutism spectrum disorders Psychosis Comorbidity Meta-analysis
This research was conducted as a part of first author’s PhD project. The authors were supported by a research grant awarded by the Spanish Ministry of Economy and Competitiveness (Grant PSI2016-80575-R), and European Union. DGSANCO. Ref.: SANCO/2014/C2/035. The suggestions made by anonymous reviewers of earlier drafts are gratefully acknowledged.
JLM conceived of the study, participated in its design and coordination and drafted the manuscript; MARF conceived of the study, participated in its design and coordination and drafted the manuscript; VMC participated in the design and interpretation of the data, and helped to draft the manuscript; MMM participated in the design and interpretation of the data, and helped to draft the manuscript; EDV participated in the interpretation of the data, performed the statistical analysis and helped to draft the manuscript; RCB participated in the design and interpretation of the data, and helped to draft the manuscript. All authors read and approved the final manuscript.
Compliance with Ethical Standards
Conflict of interest
The authors declare that they have no conflict of interest.
Ethical Approval and Informed consent
This research is based on public domain data from previous observational studies in which ethical approval and informed consent have already been obtained by the investigators.
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