ADHD Adolescent Article Attention Attention Deficit Disorder with Hyperactivity Child Cognition Cognitive Behavioral Therapy Cognitive remediation Cognitive training Computer training DSM-IV Denmark Executive Function Executive function training Female Humans Male Non-pharmacological treatment Parents Schedule for Affective Disorders and Schizophrenia Single-Blind Method Therapy, Computer-Assisted Treatment Outcome Video Games adolescent attention attention deficit disorder child child parent relation