Validity of the Social Communication Questionnaire in Adults With Intellectual Disabilities and Suspected Autism Spectrum Disorder

Abstract

This study examined the validity of the Social Communication Questionnaire (SCQ) to identify autism spectrum disorder (ASD) in 151 adults with intellectual disabilities (ID) in Germany. Sensitivities and specificities for ASD were 98/47% for the SCQ-current version and 92/22% for the SCQ-lifetime version. Sensitivities and specificities were increased to 89/66% and 78/48% by adjusting the recommended cut-points. The SCQ-current score correlated with the Scale for Pervasive Developmental Disorders in Mentally Retarded Persons and the Autism Diagnostic Observation Schedule, whereas the SCQ-lifetime score correlated with the Autism Diagnostic Interview-Revised. Our findings support the use of the SCQ-current version for ASD screening in adults with ID, although the SCQ-lifetime version should be used with caution in this population.

The Social Communication Questionnaire for adults with intellectual disability: SCQ‐AID

“…Age may be another factor contributing to low specificity rates in the SCQ, as indicated by an earlier study by Corsello et al [], in which a group of the oldest participants aged 11–16 years yielded the lowest specificity of 0.66. This finding is also consistent with previous studies in adolescent and adult samples yielding lower specificities than studies in younger children [Brooks & Benson, ; Sappok et al, ].…”

“…Specificity was relatively low for both algorithms, implying that the SCQ is over‐inclusive when screening for ASD in adults with ID. Results are consistent with previous research investigating the SCQ in samples of people with ID [Berument et al, ; Brooks & Benson, ; Sappok et al, ]. Low specificities are likely to be a problem in diagnostic tests assessing persons with ID and suspected ASD because of the symptom overlap between these two conditions.…”

“…Therefore, appropriate standardized instruments are important and may support researchers and clinicians in the diagnostic decision [Hare, Mellor, & Azmi, ; La Malfa et al, ]. Although the SCQ has been validated across a wide range of ages and levels of intellectual functioning [Chesnut et al, ; National Institute of Health and Care Excellence, ; Sappok et al, ], there are few studies examining this instrument in adults with ID, a population that is particularly at risk for ASD. Improved recognition of ASD in adults with ID may not only increase quality of life and mental health of the affected individuals and their families by providing a better chance for more appropriate treatment and care, but also may lead to improved outcomes and as a result lower costs to the economy [National Audit Office, ].…”

“…Several screening instruments have been developed with the goal of identifying ASD [see Sappok et al, ]. These include the Social Communication Questionnaire (SCQ), a well‐studied screening instrument providing information on three domains: reciprocal social interaction, communication and restricted, repetitive behaviors [Berument, Rutter, Lord, Pickles, & Bailey, ; Norris & Lecavalier, ; Rutter, Bailey, & Lord, , Sappok et al, ]. The SCQ is based on the diagnostic criteria of DSM‐IV and the items of the Autism Diagnostic Interview Revised (ADI‐R) [Le Couteur et al, ].…”

“…Numerous validation studies have shown that the SCQ is a psychometrically sound and valuable screening instrument for children and young adolescents [e.g., Chesnut, Wei, Barnard‐Brak, & Richman, ; Norris & Lecavalier, ]. However, few studies have examined it in adults with ID [Brooks & Benson, ; Sappok et al, ; Underwood, McCarthy, & Chaplin, ]. Research on adults with ID and ASD is relatively rare and there continues to be a need for more studies examining this important issue impacting individuals with ID and their families (Underwood, McCarthy & Craig, in press).…”