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Journal of Autism and Developmental Disorders

, Volume 48, Issue 9, pp 3176–3190 | Cite as

Prevalence and Characteristics of Autism Spectrum Disorder Among Spanish School-Age Children

  • Paula Morales-Hidalgo
  • Joana Roigé-Castellví
  • Carmen Hernández-Martínez
  • Núria Voltas
  • Josefa Canals
Original Paper

Abstract

The present study aims to assess the prevalence of autism spectrum disorder (ASD) in preschool and school-age children following a two-phase procedure. The screening phase was performed on a sample of 5555 children taking into account parent and teacher information. The individual assessment included the ADI-R, ADOS-2 and Wechsler scales. The estimated prevalence was 1.55% in preschoolers and 1.00% in school-age children. Between 1.84 and 2.59% of the children exhibited subclinical diagnosis. The male-to-female ratio was around 4:1. Most of the children exhibited mild and moderate nuclear symptoms, and the girls showed less severe communication problems. Previous diagnosis was found in 62–71% of the children. Prevalence estimates are close to the 1% international ratings and much higher than previous national reports suggested.

Keywords

Autism spectrum disorders Epidemiology Prevalence School-age children 

Notes

Acknowledgments

This research was supported by the Spanish Ministry of the Economy and Competitiveness and the European Regional Development Fund (ERDF; Ref. PSI2015-64837-P). It was also supported by the Ministry of Education (Grant FPU2013-01245) and the Generalitat, Government of Catalonia Universities, Researching and Information Society Department (Grant 2016FI-01144). We acknowledge the support of the Catalan Department of Education and are very grateful to all the teachers and families that participated in the EPINED project.

Author Contributions

PMH participated in the design and coordination of the study, performed the measurements, performed the statistical analysis and drafted the manuscript. JRC performed the measurements and read and approved the final manuscript. CHM and NV participated in the design, performed the measurements and read and approved the final manuscript. JC conceived of the study, participated in its design and coordination, performed the measurements, drafted the manuscript and approved the final manuscript.

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical Approval

The study protocol was approved by the Ethics Committee at the Sant Joan University Hospital (13-10-31/10proj5). Before beginning the study, we obtained permission from the Catalan Department of Education. All the schools boards contacted agreed to participate in the study. Parents received a letter informing them about the study and were asked for their written informed consent.

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© Springer Science+Business Media, LLC, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Department of Psychology, Nutrition and Mental Health Research Group (NUTRISAM), Research Center for Behavioral Assessment (CRAMC)Universitat Rovira i VirgiliTarragonaSpain

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