DIFFERENTIAL-DIAGNOSIS BETWEEN ATTENTION-DEFICIT HYPERACTIVITY DISORDER AND PERVASIVE DEVELOPMENTAL DISORDER - NOT OTHERWISE SPECIFIED/

The lack of clarity in diagnostic classification and the lack of speci ficity of assessment devices deter accurate identification of children with Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NO S). The current study was designed to assess the utility of the Person ality Inventory for Children (PIC) and the Conners Parent Rating Scale (CPRS-48) in differentiating PDD-NOS from Attention Deficit Hyperacti vity Disorder (ADHD), disorders with overlapping symptom constellation s. Subjects were 44 children recruited from a tertiary-care center wit h the diagnosis of ADHD or PDD-NOS. Results showed significant differe nces between groups on PIC scales assessing internalizing behaviors, s ocial skills, and unusual affect and behavior, There were no group dif ferences on the externalizing or learning scales of the CPRS-48. Discr iminant function analysis using preselected PIC variables yielded a co rrect group classification of 92.7%. The PIC appears to be a useful to ol in the differential diagnosis between PDD-NOS and ADD, while the CP RS-48, a commonly used screening measure for attentional and behaviora l disorders, does not.