A qualitative and quantitative virtual reality usability study for the early assessment of ASD children.

The diagnosis of autism spectrum disorder (ASD) is usually done using structured and semi-structured interviews directed to children and caregivers. These procedures are administered by certified clinicians who have expertise in the assessment of ASD. However, on one side, semi-structured procedures addressed to children are usually administered in settings requiring ecological validity such as the laboratory; on the other side, structured interviews to caregivers rely on selfreport that might be affected by psychological response biases. There is the need to fulfil aforementioned needs, improving ASD assessment procedures through the use of both ecological settings and objective measures. The present study aims to investigate the usability of a novel procedure to assess ASD based on virtual reality (VR) and quantitative measures. 20 children with ASD and 20 children with typical development (TD) performed four basic tasks in the VR system Cave Assisted Virtual Environment (CAVET) while an examiner analysed the usability of the application as well as children's user experience. Quantitative behavioural variables related to children's performance across tasks were measured. Included tasks required children to interact in the virtual environment with childlike objects. Findings demonstrated that VR application was promising for the assessment of ASD due to good usability in three tasks out of four and positive user experience. Moreover, quantitative behavioural outcomes revealed differences between groups on time spent playing and accuracy across tasks. Quantitative and qualitative usability studies improve the effectiveness of new objective and technology-based ASD assessment procedures, in particular when children represent the population target.