Overlaps, prevalence and comorbidity Overlapping symptoms It is now recognised that ASD and personality disorders (PDs) have a variety of factors in common. However, the exact nature of the relationship between ASD and the PDs remains unclear. Differentiating between ASD in adolescence and adulthood and PDs can often be challenging due to the similarity in symptomatology. For instance: - PDs belonging to cluster A, such as schizoid or schizotypal, exhibit odd behaviours