One of the most prevalent neurodevelopmental disorders in children is Attention Deficit Hyperactivity Disorder (ADHD), which is closely followed by Autism Spectrum Disorders (ASD). The DSM-5's diagnostic change, which permits a combination diagnosis of ADHD and ASD, introduces new clinical issues related to diagnostic overshadowing, the reliability of clinical judgement, and the potential delay in an ASD diagnosis in kids who present with ADHD. By contrasting children with ASD with and without comorbid ADHD with children presenting ADHD only and children with usual development, we attempted to disentangle the clinical phenotype and uniqueness of the two cooccurring diseases in relation to autism features and empathy. A total of 198 male children between the ages of 6 and 12 were given the child versions of the Autism Quotient (C-AQ) and the Empathy Quotient (CEQ) having verbal abilities commensurate with age and average IQ. Children with ASD and children with ASD+ADHD did not significantly differ in their C-AQ total and subscale scores, C-EQ, or C-EQ scores, according to a univariate analysis, but children with ADHD alone displayed a phenotype that was intermediate between ASD and TD. A Receiver Operating Characteristic (ROC) analysis was used to distinguish between the various phenotypes. Our results support the validity of the C-AQ and C-EQ as behavioural indicators to distinguish TD and an ADHD state from ASD (independent of comorbid ADHD). Intriguingly, in our group, the presence of ADHD does not worsen the clinical phenotype in terms of the distribution of autism features and empathy, indicating that the psychological indicators identified by the two quantitative instruments are accurate regardless of ADHD characteristics. The translational efforts to provide more individualised treatments and prevention measures will benefit from this evidence.
