Comprehensive evaluation of attention deficit disorder with and without hyperactivity as defined by research criteria.

Children with attention deficit disorder with hyperactivity (ADD+H; N = 48) were compared with those without hyperactivity (ADD-H; N = 42), as well as with learning disabled and control children, on an extensive battery of interviews, behavior ratings, tests, and direct observations. ADD+H children had more externalizing and internalizing symptoms by parent and teacher report, were more off task during vigilance testing, and had more substance abuse, ADD+H, and aggression among their relatives than did the other groups. ADD-H children were more day-dreamy and lethargic by teacher report, more impaired in perceptual-motor speed, and had more anxiety disorders among their relatives than did ADD+H children. Results indicate that these 2 types of ADD may be separate, distinct childhood disorders rather than subtypes of a common attention deficit.