Autism spectrum disorder (ASD) is a neurodevelopmental disorder involving a set of alterations in brain development that vary from one individual to another. The term ‘spectrum’ indicates precisely the wide variability of manifestations in terms of type and severity.

Unlike clinical assessment, rating scales have a standardised procedure and qualitative, normative scores. Therefore, they can be assessed according to psychometric parameters. Starting from these considerations, the present work intends to subject the ‘Autism Rating Scale For Adults’ (ARSA), designed and constructed by one of the authors (G.M.G.), to some statistical evaluations.

The aim is to determine the scale's accuracy in identifying subjects, adolescents and adults, previously diagnosed as autistic, bearing in mind that the forms of autism, already very diversified on a clinical level, present themselves differently about age: in adolescents and young adults, for example, peculiar symptomatological characteristics are highlighted, with the exacerbation of symptoms especially at times of change (end of school) and in the management of free time.