Cognitive Profile in Autism and ADHD: A Meta-Analysis of Performance on the WAIS-IV and WISC-V

OBJECTIVE: Previous research has suggested that neurodevelopmental conditions may be associated with distinctive cognitive profiles on the Wechsler intelligence tests (of which the most recent editions are the WAIS-IV and WISC-V).

However, the extent to which a cognitive profile can be reliably identified for individuals meeting criteria for autism or ADHD remains unclear.

The present review investigated this issue.

METHOD: A search was conducted in PsycInfo, Embase, and Medline in October 2022 for papers reporting the performance of children or adults diagnosed with autism or ADHD on the WAIS-IV or the WISC-V. Test scores were aggregated using meta-analysis.

RESULTS: Scores were analyzed from over 1,800 neurodivergent people reported across 18 data sources.

Autistic children and adults performed in the typical range for verbal and nonverbal reasoning, but scored ~1 SD below the mean for processing speed and had slightly reduced scores on working memory.

This provides evidence for a “spiky” cognitive profile in autism.

Performance of children and adults with ADHD was mostly at age-expected levels, with slightly reduced scores for working memory.

CONCLUSION: Although the pattern of performance on the Wechsler tests is not sufficiently sensitive or specific to use for diagnostic purposes, autism appears to be associated with a cognitive profile of relative strengths in verbal and nonverbal reasoning and a weakness in processing speed.

Attention deficit hyperactivity disorder appears less associated with a particular cognitive profile.

Autistic individuals may especially benefit from a cognitive assessment to identify and support with their strengths and difficulties.