Evaluating Computerised Assessment of Motor Imitation (CAMI) for identifying autism-specific difficulties not observed for attention-deficit hyperactivity disorder or neurotypical development.

Researchers tested a 1-minute computer game called CAMI that measures how well children copy movements. They found that autistic children performed differently on this game compared to children with ADHD or typical development. The game correctly identified autism in 8 out of 10 children when compared to typical children, and 7 out of 10 when compared to children with ADHD. This suggests CAMI could be a quick, affordable tool to help distinguish autism from ADHD, which can be challenging for doctors.

This cross-sectional study evaluated the Computerised Assessment of Motor Imitation (CAMI), a brief 1-minute videogame-based tool, for distinguishing autism spectrum disorders from ADHD and neurotypical development. The study included 183 children aged 7-13 years across three groups: ASD (with/without ADHD), ADHD-only, and neurotypical controls. Results showed children with ASD performed significantly worse on CAMI compared to both neurotypical children and those with ADHD-only, regardless of co-occurring ADHD. CAMI demonstrated diagnostic accuracy with 80% true positive rate for distinguishing ASD from neurotypical development and 70% for distinguishing ASD from ADHD.

Poor CAMI performance correlated with increased autism traits, particularly social affect and repetitive behaviours, but not with ADHD symptoms or general motor ability.

CAMI shows promise as a brief, scalable assessment tool that could assist in differentiating ASD from ADHD, potentially reducing diagnostic delays and misdiagnosis. The tool's brevity and computerised format could make autism assessment more accessible in various clinical settings.

Cross-sectional design limits understanding of developmental trajectories. Sample characteristics and demographic details not fully reported in abstract. Validation in independent samples and different age groups needed before clinical implementation.

Reliable and specific biomarkers that can distinguish autism spectrum disorders (ASDs) from commonly co-occurring attention-deficit/hyperactivity disorder (ADHD) are lacking, causing misses and delays in diagnosis, and reducing access to interventions and quality of life. To examine whether an innovative, brief (1-min), videogame method called Computerised Assessment of Motor Imitation (CAMI), can identify ASD-specific imitation differences compared with neurotypical children and children with ADHD. This cross-sectional study used CAMI alongside standardised parent-report (Social Responsiveness Scale, Second Edition) and observational measures of autism (Autism Diagnostic Observation Schedule-Second Edition; ADOS-2), ADHD (Conners) and motor ability (Physical and Neurological Examination for Soft Signs). The sample comprised 183 children aged 7-13 years, with ADHD (without ASD), with ASD (with and without ADHD) and who were neurotypical.

Regardless of co-occurring ADHD, children with ASD showed poorer CAMI performance than neurotypical children (< 0.0001; adjusted= 0.28), whereas children with ADHD and neurotypical children showed similar CAMI performance. Receiver operating curve and support vector machine analyses showed that CAMI distinguishes ASD from both neurotypical children (80% true positive rate) and children with ADHD (70% true positive rate), with a high success rate significantly above chance. Among children with ASD, poor CAMI performance was associated with increased autism traits, particularly ADOS-2 measures of social affect and restricted and repetitive behaviours (adjusted= 0.23), but not with ADHD traits or motor ability. Four levels of analyses confirm that poor imitation measured by the low-cost and scalable CAMI method specifically distinguishes ASD not only from neurotypical development, but also from commonly co-occurring ADHD.