A comparison of behavioral and attentional functioning in children diagnosed as hyperactive or learning-disabled.

The attentional and behavioral functioning of children diagnosed as hyperactive (ADHD), learning-disabled (LD), and hyperactive/learning-disabled were compared, using standardized behavior rating scales across raters and settings, and results from a battery of standardized neuropsychological tests. The ADHD and LD groups were "pure" samples with respect to comorbidity. Multiple discriminant-function analyses on the behavioral and neuropsychological data showed that one variate made clear-cut discriminations among and between each of the three groups. The constructs self-regulation, task accuracy/planning/speed, and aggression differentiated the three groups, while sustained attention did not. The results lend strong support to the validity of ADHD as a diagnostic entity apart from LD, and suggest that poor self-regulation and inhibition of behavior may be the hallmark of ADHD.