BACKGROUND

This study is the first to evaluate the Social Communication Questionnaire (SCQ) and the Developmental Behaviour Checklist-Autism Screening Algorithm (DBC-ASA) in the same sample of school-aged children with intellectual disability (ID) with and without Pervasive Developmental Disorders (PDDs).

METHOD

Parents of 49 children (36 with PDDs and 13 with ID) completed a survey that included a demographic form, a measure of adaptive behaviour (the SIB-R), the SCQ, and the DBC-ASA.

RESULTS

According to established cut-offs, the SCQ's sensitivity was .92 and specificity was .62, and the DBC-ASA's sensitivity was .94 and specificity was .46. Six of the seven false positives on the DBC-ASA had DBC Total Problem Behaviour scores above the clinical cut-off. By contrast, all six true negatives had Total Problem Behaviour scores below the clinical cut-off. No such pattern was noted for the SCQ.

CONCLUSION

While both instruments have good psychometric properties, the results of this study suggest that clinicians and researchers should exercise caution when utilising the DBC-ASA to screen for PDDs in individuals with significant behaviour problems, as this could decrease its diagnostic validity.