Pervasive Developmental Disorder - Not Otherwise Specified (PDD-NOS) is one of the pervasive developmental disorders and autism spectrum disorders.
PDD-NOS is a diagnosis for people who are well-described by the "PDD" label, but cannot be categorized by any other disorder. It is usually milder than autism and has similar symptoms to autism, with some symptoms present, and others absent. This disorder is sometimes called "atypical autism" by autism specialists. The boundaries between PDD-NOS and non-autistic conditions are not fully resolved.
PDD-NOS is often incorrectly referred to as simply “PDD.” The term PDD refers to the class of conditions to which the five disorders belong to. PDD is not itself a diagnosis, while PDD-NOS is a diagnosis. To further complicate the issue, PDD-NOS can also be referred to as “atypical personality development,” “atypical PDD,” or “atypical Autism”.
Because of the "NOS", which means "not otherwise specified", it is hard to describe what PDD-NOS is, other than it being an autism spectrum disorder (ASD). Some people diagnosed with PDD-NOS are close to having Asperger syndrome, but do not quite fit. Others have near full fledged autism, but without some of its symptoms. The psychology field is considering creating several subclasses within PDD-NOS.
Symptoms of PDD may include communication problems such as:
* Difficulty using and understanding language
* Difficulty relating to people, objects, and events; for example, lack of eye contact or pointing behavior
* Unusual play with toys and other objects
* Difficulty with changes in routine or familiar surroundings
* Repetitive body movements or behavior patterns
Diagnosis is usually done during early childhood. Some clinicians use PDD-NOS as a "temporary" diagnosis for children under the age of 5, when for whatever reason there is a reluctance to diagnose autism. There are several justifications for this: very young children have limited social interaction and communication skills to begin with, therefore it can be tricky to diagnose milder cases of autism in toddlerhood. The unspoken assumption is that by the age of 5, unusual behaviors will either resolve or develop into diagnosable autism. However, some parents view the PDD label as no more than a euphemism for autism spectrum disorders, problematic because this label makes it more difficult to receive aid for Early Childhood Intervention.
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