Table of Contents
Epidemiology Research International
Volume 2011, Article ID 412150, 8 pages
Research Article

Efficiency of a Small Size Screening Instrument in Identifying Children with Autism Spectrum Disorders in a Large Population of Twins

1Research Unit Department of Child and Adolescent Psychiatry, Odense University Hospital, University of Southern Denmark, Hunderupvej 116, 5230 Odense M, Denmark
2Institute of Regional Health Services Research, University of Southern Denmark, J. B. Winsløvs Vej 19, 5000 Odense C, Denmark
3Odense Patient data Exploratory Network, Odense University Hospital, Institute of Clinical Research, University of Southern Denmark, J. B. Winsløvs Vej 19, 5000 Odense C, Denmark

Received 28 December 2010; Revised 24 February 2011; Accepted 4 March 2011

Academic Editor: H. T. Sørensen

Copyright © 2011 Claudia Nordenbæk et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


This study evaluated the effectiveness of a short scale in screening for autism spectrum disorders (ASDs) and documented the prevalence of ASD in twins born in 1988–2000 as registered in the Danish Psychiatric Central Research Registry (DPCRR). Five child behaviour checklist (CBCL) items were used in a first-phase screening of all twins born 1988–2000, recruited from the Danish Twin Registry. In Denmark, nearly all psychiatric diagnoses are reported to DPCRR, and the two registers were linked for validation purposes. Parents of >16,000 twins responded (68.4%); among the twins, 108 were registered with ASD. The optimal cut-off score of two out of ten yielded a sensitivity of 79.6% and a specificity of 81.4%. The registry linkage identified 176 twins with ASD (point prevalence = 0.72%). This study demonstrates that it is feasible to screen large populations for ASD with a 5-item questionnaire. The prevalence of registered ASD in twins corresponds to recent population-based studies in singletons.