Psychometric evaluation of the Autism Symptom Dimensions Questionnaire

Abstract

This study re-examined a caregiver-reported measure of autism symptoms called the Autism Symptom Dimensions Questionnaire (ASDQ). The ASDQ was evaluated using two large samples and a small series of children receiving intensive behavioral intervention. The large samples included a national US population sample and a national clinical sample with over-representation of individuals from historically underrepresented backgrounds who were using public insurance. Both samples included young people with autism spectrum disorder (ASD) and young people with non-ASD developmental conditions.

The ASDQ was evaluated in terms of its structure, reliability, validity, and sensitivity to change. The first major finding was that the structure of the ASDQ replicated across both large samples and was consistent with prior research. The second major fining was that the ASDQ showed very good reliability, including good ability to measure across low, average, and high score ranges, and good stability of scores across time. The third major finding was that the ASDQ showed moderate to strong associations with other measures of autism symptoms, even when those measures came from different modalities (e.g. clinician observation). The fourth major finding was that the ASDQ had very good ability to screen for ASD in the population sample but had weaker validity for detecting ASD in the clinical sample. The last major finding from the small case series was that the ASDQ showed the ability to detect reliable change in autism symptoms and social communication/interaction behavior in children receiving intensive behavioral intervention.