Pervasive Developmental Disorder
The term "PDD" is widely used by professionals to refer to children with autism and related disorders; however, there is a great deal of disagreement and confusion among professionals concerning the PDD label. Diagnosis of PDD, including autism or any other developmental disability, is based upon the Diagnostic and Statistical Manual of Mental Disorders - Fourth Edition (DSM-IV), published by the American Psychiatric Association (Washington, DC, 1994), and is the main diagnostic reference of mental health professionals in the U.S.
According to the DSM-IV, the term "PDD" is not a specific diagnosis, but an umbrella term under which the specific diagnoses are defined.
Diagnostic labels are used to indicate commonalities among individuals. The key defining symptom of autism that differentiates it from other syndromes and/or conditions is substantial impairment in social interaction (Frith, 1989). The diagnosis of autism indicates that qualitative impairments in communication, social skills, and range of interests and activities exist. As no medical tests can be performed to indicate the presence of autism or any other PDD, the diagnosis is based upon the presence or absence of specific behaviors. For example, a child may be diagnosed as having PDD-NOS if he or she has some behaviors that are seen in autism, but does not meet the full criteria for having autism. Most importantly, whether a child is diagnosed with a PDD (like autism) or a PDD-NOS, his/her treatment will be similar.
Autism is a spectrum disorder, with symptoms ranging from mild to severe. As a spectrum disorder, the level of developmental delay is unique to each individual. If a diagnosis of PDD-NOS is made, rather than autism, the diagnosticians should clearly specify the behaviors present. Evaluation reports are more useful if they are specific and become more helpful for parents and professionals in later years when reevaluations are conducted.
Ideally, a multidisciplinary team of professionals should evaluate a child suspected of having autism. The team may include, but may not be limited to, a psychologist or psychiatrist, a speech pathologist and other medical professionals, including a developmental pediatrician and/or neurologist. Parents and teachers should also be included, as they have important information to share when determining a child's diagnosis.
In the end, parents should be more concerned that their child find the appropriate educational treatment based on their needs, rather than spending too much effort to find the perfect diagnostic label. Most often, programs designed specifically for children with autism will produce greater benefits, while the use of the general PDD label can prevent children from obtaining services relative to their needs.
Also within each diagnosis is the ASA Panel of Professional Advisors' recommended definition of the autism spectrum and related syndromes and conditions, which is not to be used for research purposes but rather for defining the demographics of the ASA’s membership. The ASA is not attempting to represent individuals with related syndromes or conditions who do not also have autism, but rather those where autism is present in related syndromes and conditions, and where autism is the defining syndrome (e.g., autism-Asperger’s). The rationale for this position is due to the unique service needs that are imperative for individuals with autism that may not be required of the cohort disability. (See also "General Standards of Care for Individuals with Autism Throughout the Lifespan.")
Reprinted with the permission of the Autism Society.