Autism is the most common subtype of a group of conditions that are known collectively as Pervasive Developmental Disorders. Pervasive Developmental Disorders (PDD) is the technical term used to describe a variety of disorders that severely impact on the social, emotional and language development of a child. Children with PDD do not interact in the way that we expect children to interact; they do not look at others; they do not express normal emotions. It is as if they are in a world of their own.

Pervasive Developmental Disorders includes Autistic disorder, Asperger’s disorder, Rett’s disorder, PDD-NOS and others. What these disorders all have in common is that they first appear in childhood and they impact the social and emotional development of the child. While it may be confusing, there are a variety of other terms used by both professionals and lay people that generally mean the same thing. For example, Autistic Disorder is also known as autism, autism spectrum disorder (ASD) and global developmental delay. The important point to remember is that these terms refer to the same type of thing. The reason for the variety of terms is that researchers, clinicians and physicians are struggling to find terminology that accurately describes the range and severity of behaviour that children with these conditions can exhibit.

Autism specifically, garners the most attention in the popular press. However, while the rate of autism has increased compared to 25 years ago, it still remains a relatively rare condition. Autistic disorders occur in less than 1 percent of the general population or about 5 children per 10,000.

The identification of autism is not based on a "medical test" such as collecting blood or completing a brain scan. The identification of this condition is based on gathering a complete developmental history, the use of questionnaires, structured interviews and standardized tests, as well as observations of the child based on an understanding of normal child development and the pattern of behaviour that children with autism exhibit. Thus, identification is best left to a professional with experience in the diagnosis of this condition.

There is a range of severity for PDD. A child can have a mild, moderate or severe form of autism for example. Autism is a life long condition, there is no "cure". These children will change and grow but at a rate that is different from other children. However, the autism will never disappear.

While not disappearing, there are treatment options that can be helpful for the child. The most common form of treatment for autism is behaviour modification. Behaviour modification is also referred to as Applied Behaviour Analysis (ABA) and Intensive Behavioural Intervention (IBI). Gains using this method are often reported, but as with any treatment there are limits to the amount of progress that can be made. Further, the outcome with any individual child will vary tremendously based on the severity of the autism that the child has.

Parents need to accept that their child will have autism for their entire life. Parents need to make plans for their child. This means learning about the condition, working with the school system, agencies and others to achieve your child’s maximum potential in the present and for their future.

If your child is identified with a pervasive developmental disorder contact you local community support agency. Lastly, as your child reaches adulthood, an updated assessment may be needed to access income tax benefits and other support.