Attention-Deficit/Hyperactivity Disorder (ADHD) is an externalizing disorder beginning in childhood with symptoms and impairment persisting into adulthood for many individuals. Although ADHD is identifiable and diagnostically valid during the preschool years, the majority of the research has focused on treating school-aged children. Some research suggests that behavioral parent training (BPT) programs are efficacious in treating young children. Yet, results are inconsistent and previous research has methodological limitations that restrict interpretations of the data. Parent-Child Interaction Therapy (PCIT), a widely-disseminated evidence-based BPT program for young children with disruptive behavior problems, incorporates components (e.g., in vivo coaching) that may be particularly effective for this population. Therefore, the current study investigated the effects of PCIT on ADHD symptoms and impairment utilizing a non-concurrent multiple baseline design across 4 children (ages 5 and 6). Results demonstrated a visible increase in child on-task behavior in 50% of the children, a decrease in maternal report of child ADHD symptoms, impairment, and ODD symptoms, and maternal report of treatment satisfaction. These findings suggest that PCIT may reduce attention and hyperactivity/impulsivity problems in addition to oppositional behaviors. Despite these promising results, the inconsistent findings pertaining to on-task behavior, persistence of school difficulties and parenting stress demonstrate the need for further intervention. Additionally, limitations pertaining to the design, sample, and measurement are discussed
