Pervasive Development Dosorders Not Otherwise Specified (PDD-NOS), along with Asperger’s Syndrome (AS) and Classic Autism, is a part of the Autism Spectrum. People who are diagnosed with PDD-NOS exhibits symptoms which are similar to those who have Autism but at the same time, do not exactly meet the criteria for AS or Classic Autism. In other words, when there is not enough evidence to support a diagnosis for Autism, yet the symptoms are pronounced enough, individuals may get diagnosed with PDD-NOS. It has been criticized as being a catch-all diagnosis.
The DSM or the Diagnostic and Statistical Manual of Mental Disorders define PDD-NOs as follows:
“This category should be used when there is a severe and pervasive impairment in the development of reciprocal social interaction or verbal and nonverbal communication skills, or when stereotyped behavior, interests, and activities are present, but the criteria are not met for a specific pervasive developmental disorder, schizophrenia, schizotypal personality disorder, or avoidant personality disorder. For example, this category includes “atypical autism” –presentations that do not meet the criteria for autistic disorder because of late age of onset, atypical symptomatology, or subthreshold symptomatology, or all of these.”
It should be pointed out that at the time of writing, professionals do not have a consensus as to how to correctly diagnose PDD-NOS and that there are not many succint diagnostic tools available. Academics and professionals alike criticize the DSM-IV-TR’s definition as being too weak.
Helpful PDD-NOS reading materials:
PDD-NOS checklist (read skeptically)
Volkmar et al. (2004) Autism and Pervasive Disorders (Free access Academic Journal Article)
Quinn (2000) Pervasive Developmental Disorders: An Altered Perspective (A book worth buying)
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Inspiring People with Autism:
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