Pervasive Developmental Disorder

Pervasive Developmental Disorder, or PDD, is the umbrella term used to cover the whole family of autistic spectrum disorders - including autism and Asperger Syndrome. Within this group there is a subgroup called NOS - not otherwise specified - which covers the conditions which do not quite meet the diagnostic criteria for autism or Asperger Syndrome. Because PDD covers such a wide spectrum, it presents very differently from child to child.