What is pdd-nos?
Pervasive Developmental Disorder, Not Otherwise Specified (PDD-NOS) was introduced to classify individuals showing problems and disabilities related to autism but that fall short of the number of characteristics or range of impaired areas that is required for a definition of autism. A child could have a diagnosis of PDD-NOS if he shows only 5 of the 12 characteristics listed under autism or if he has more than 6 characteristics spread over the 3 areas but only 1 in the social area. Another way to think of PDD-NOS is as a subthreshold autism or a child who has atypical symptoms that do not quite fit with the 12 characteristics one assesses under autism.
