Methods
ADHD
 A multicenter randomized controlled study was conducted using system-based group therapy with 62 parents of preschool children with ADHD aged four to six years. ADHD symptoms, behavioral and emotional problems, and social functioning were compared with 61 control children whose parents did not receive training by applying the ADHD Rating Scale (ADHD-RS), Strengths and Difficulties Questionnaire (SDQ), and Questionnaire-Children with Difficulties (QCD) at the time of subject entry and at two and six months of entry, respectively. 