The Autism Symptom Dimensions Questionnaire: Development and psychometric evaluation of a new, open‐source measure of autism symptomatology

Abstract

Aim To describe the development and initial psychometric evaluation of a new, freely available measure, the Autism Symptom Dimensions Questionnaire (ASDQ). Method After development and revision of an initial 33‐item version, informants completed a revised 39‐item version of the ASDQ on 1467 children and adolescents (aged 2–17 years), including 104 with autism spectrum disorder (ASD). Results The initial 33‐item version of the ASDQ had good reliability and construct validity. However, only four specific symptom factors were identified, potentially due to an insufficient number of items. Factor analyses of the expanded instrument identified a general ASD factor and nine specific symptom factors with good measurement invariance across demographic groups. Scales showed good‐to‐excellent overall and conditional reliability. Exploratory analyses of predictive validity for ASD versus neurotypical and other developmental disability diagnoses indicated good accuracy for population and at‐risk contexts. Interpretation The ASDQ is a free and psychometrically sound informant report instrument with good reliability of measurement across a continuous range of scores and preliminary evidence of predictive validity. The measure may be a useful alternative to existing autism symptom measures but further studies with comparison of clinical diagnoses using criterion‐standard instruments are needed. What this paper adds The Autism Symptom Dimensions Questionnaire (ASDQ) is a new, freely available measure of autism symptoms. The ASDQ showed reliable and accurate measurement of autism symptoms. The measure had good screening efficiency for autism spectrum disorder relative to other developmental conditions.

Asperger syndrome and clinical heterogeneity: Reflections on the past, present, and future

“…Further, instruments used to quantify Asperger syndrome, which continue to be utilized for assessing autism spectrum disorder, lack the sensitivity to detect subtle symptom expressions. More importantly, the majority of existing instruments do not provide a comprehensive characterization of distinct, fine-grained facets of social functioning and restricted and repetitive behavior domains, 3,4 obscuring qualitative distinctions between individuals diagnosed with Asperger syndrome and other forms of autism.…”

A Comparison of Parent Reports, the Mental Synthesis Evaluation Checklist (MSEC) and the Autism Treatment Evaluation Checklist (ATEC), with the Childhood Autism Rating Scale (CARS)

“…An early diagnosis and personalized interventions both play crucial roles in fostering positive outcomes for individuals with ASD [ 6 , 7 , 8 ]. There is a significant interest in using parent reports to assess the efficacy of ASD treatments [ 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. Parents’ assessments improve the scope and granularity of outcome measures with little additional cost.…”

A first step in open‐source measures of autism symptoms: Promises to keep

“…The autism sample was both very small and highly heterogeneous; a total of 104 children represented a range of 2 to 17‐year‐olds, with skills from minimal verbal abilities to fluent speech (for example, only 14 autistic children aged between 9 and 11 years spanned the full range of verbal ability). Furthermore, although predictive validity of parent‐reported diagnosis of autism versus no autism was good overall, when a cutoff with high specificity was created (98%), only 56% of the sample with autism was identified 1 …”

“…However, these measures are copyrighted and often expensive, which limits their use in large scale studies and in lower income regions. Thus, many factors contribute to the urgency that underlies the ambitious creation of a new instrument, the Autism Symptom Dimensions Questionnaire (ASDQ) 1 …”