Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2012;7(7):e41280.
doi: 10.1371/journal.pone.0041280. Epub 2012 Jul 20.

Autism spectrum disorders in the Stockholm Youth Cohort: design, prevalence and validity

Selma Idring  1 , Dheeraj Rai, Henrik Dal, Christina Dalman, Harald Sturm, Eric Zander, Brian K Lee, Eva Serlachius, Cecilia Magnusson
Affiliations

Autism spectrum disorders in the Stockholm Youth Cohort: design, prevalence and validity

Selma Idring et al. PLoS One. 2012.

Abstract

Objective: Reports of rising prevalence of autism spectrum disorders (ASD), along with their profound personal and societal burden, emphasize the need of methodologically sound studies to explore their causes and consequences. We here present the design of a large intergenerational resource for ASD research, along with population-based prevalence estimates of ASD and their diagnostic validity.

Method: The Stockholm Youth Cohort is a record-linkage study comprising all individuals aged 0-17 years, ever resident in Stockholm County in 2001-2007 (N = 589,114). ASD cases (N = 5,100) were identified using a multisource approach, involving registers covering all pathways to ASD diagnosis and care, and categorized according to co-morbid intellectual disability. Prospectively recorded information on potential determinants and consequences of ASD were retrieved from national and regional health and administrative registers. Case ascertainment was validated through case-note review, and cross validation with co-existing cases in a national twin study.

Results: The 2007 year prevalence of ASD in all children and young people was 11.5 per 1,000 (95% confidence interval 11.2-11.8), with a co-morbid intellectual disability recorded in 42.6% (41.0-44.2) of cases. We found 96.0% (92.0-98.4) of reviewed case-notes being consistent with a diagnosis of ASD, and confirmed ASD in 85.2% (66.2-95.8) of affected twins.

Conclusions: Findings from this contemporary study accords with recently reported prevalence estimates from Western countries at around 1%, based on valid case ascertainment. The Stockholm Youth Cohort, in light of the availability of extensive information from Sweden's registers, constitutes an important resource for ASD research. On-going work, including collection of biological samples, will enrich the study further.

PubMed Disclaimer

Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Figure 1
Figure 1. The year 2007 prevalence of autism spectrum disorders (ASD) in the Stockholm Youth Cohort.
Points indicate the observed prevalence (cases per 1,000) for each age (4–23 years). An empirical mode decomposition smoothing curve is superimposed. A) ASD prevalence with or without co-morbid intellectual disability B) ASD prevalence by gender C) ASD prevalence by gender with or without co-morbid intellectual disability.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. International Statistical Classification of Diseases and Related Health Problems 10th revision. World Health Organisation. 2010. Available: http://apps.who.int/classifications/icd10/browse/2010/en. Accessed 2011 Dec 13. - PubMed
    1. American Psychiatric Association. Diagnostic and Statistical Manual of Mental Disorders (4th edition) (DSM-IV). Washington DC.: American Psychiatric Association. 866 p. 1994.
    1. Fombonne E. Epidemiology of pervasive developmental disorders. Pediatr Res. 2009;65:591–598. - PubMed
    1. Prevalence of autism spectrum disorders-Autism and Developmental Disabilities Monitoring Network, 14 sites, United States. MMWR Surveill Summ. 2008;61:1–19. - PubMed
    1. Baird G, Simonoff E, Pickles A, Chandler S, Loucas T, et al. Prevalence of disorders of the autism spectrum in a population cohort of children in South Thames: the Special Needs and Autism Project (SNAP). Lancet. 2006;368:210–215. - PubMed

Publication types