The validity of the social communication questionnaire in adults with intellectual disability

This study assessed the validity of the Social Communication Questionnaire (SCQ) in a sample of 69 adults, aged 18–40 years old. Participants included 21 adults diagnosed with an autism spectrum disorder (ASD) and intellectual disability (ID), and 48 individuals diagnosed with ID and no diagnosis of an ASD. The SCQ yielded a sensitivity of .71 and a specificity of .77 at the authors’ recommended cutoff score of 15 (Berument et al., 1999). However, when sensitivity was prioritized over specificity, the optimal cutoff score was 12, which yielded a sensitivity of .86 and a specificity of .60. The internal consistencies of the total scale (α = .87), the social interaction subscale (α = .83), and the restricted repetitive behavior subscale (α = .81) were good, but the communication subscale performed poorly (α = .48). The SCQ shows promise as a screening measure for adults with ID whose early developmental history may be unavailable. A lower cutoff score than the authors originally proposed is recommended in adults.

► Few studies have examined the SCQ in adults.
► The SCQ exhibited fair discriminative validity in adults with ID.
► Internal consistencies of the SCQ and social and RRB domains was high.
► However, the communication domain performed poorly.
► A lower cut off score for adults with ID is recommended.