Objective: This study investigated the psychometric properties of the Social Communication Questionnaire (SCQ) in a sample of children with Down syndrome (DS), many of whom had a co-occurring autism spectrum disorder (ASD). The SCQ is a widely used ASD screening measure; however, its measurement properties have not been comprehensively evaluated specifically in children with DS, a group that seems to be at higher risk for an ASD. Methods: Exploratory and confirmatory factor analyses, scale reliability, convergent and discriminant correlations, significance tests between groups of children with DS and DS + ASD, and diagnostic accuracy analyses were conducted. Results: Factor analyses identified 2 reliable factors that we labeled Social-Communication and Stereotyped Behavior and Unusual Interests. Pearson correlations with Autism Diagnostic Interview-Revised subscales indicated support for the SCQ's convergent validity and some support for the discriminant validity of the factor-based scales. Significance tests and receiver operating characteristic analyses indicated that children with DS + ASD obtained significantly higher SCQ factor-based and total scores than children with DS alone, and that the SCQ Total Score evidenced good sensitivity and adequate specificity. Conclusions: Results indicated initial psychometric support for the SCQ as an ASD screening measure in children with DS. The SCQ should be considered as part of a multimethod evaluation when screening children with DS.
From the *Division of Neurodevelopmental and Behavioral Pediatrics, Department of Pediatrics, University of Rochester School of Medicine and Dentistry, Rochester, NY; †School Psychology Program, Department of Psychology, Rochester Institute of Technology, Rochester, NY; ‡Department of Psychology, Hofstra University, Hempstead, NY.
Received August 2011; accepted November 2011.
This study was funded in part by AUCD/RTO1 2005-1/2-08, Hyman, PI.
Disclosure: The authors declare no conflict of interest.
Address for reprints: Vincent Pandolfi, PhD, School Psychology Program, Department of Psychology, Rochester Institute of Technology, Building 1 Room 3378, 18 Lomb Memorial Drive, Rochester, NY 14623-5604; e-mail: firstname.lastname@example.org.