“…Socialisation deficits, as measured by the Vineland Adaptive Scales (VABS), were observed by Stein and his colleagues among boys, aged 4 to 16 years, with ADHD or ADD and co‐morbid appositional defiant and/or conduct disorder, although not among those with ADHD or ADD only (Stein, Szumowski, Blondis, & Roizen, 1995). Roizen, Blondis, Irwin, and Stein (1994) also investigated adaptive behaviour in a group of children ( n =104), aged 6 to 16 years, using the VABS, and found that socialisation deficits, relative to intellectual potential, were most marked in the group of children with co‐morbid ADHD, disruptive disorders, and learning difficulties. The findings suggest that within the realm of externalising behaviour disorders, the adolescent with co‐morbid ADHD and ODD/CD may be the most severely disadvantaged with respect to the acquisition of skills and satisfying interpersonal relationships.…”