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Autism, Autistic Spectrum Disorders (ASD) and Pervasive Developmental Disorders (PDD)

What are the autistic spectrum disorders (ASD)?
Autism spectrum disorders, or ASD, are also called pervasive developmental disorders (PDD) because they involve delay in many areas of development. PDD or ASD is a category that includes five different disorders of development, each with differing severities and patterns:

For more information on ASD and PDD:

What is autism or autistic disorder?
Autism is the most common autism spectrum disorder.  People with autism have differences in the development of their thinking, language, behavior and social skills. The differences appear before age three, and can be diagnosed by 18 months. For a diagnosis of autism, a child must have a specified number of symptoms in these areas:

If you think your child may have these traits, talk to your health care provider and find out how to have your child evaluated.

What is Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS)?
PDD-NOS, also called atypical autism or mild autism, means having differences in some of the same areas as in autism, only not to such a great extent. A child with PDD-NOS does not meet the criteria for any other specific PDD/ASD.

What is Rett Syndrome?
See YourChild: Rett Syndrome.

What is Asperger syndrome?
See YourChild: Asperger syndrome.

What is Childhood Disintegrative Disorder (CDD)?
See these resources:

How common are the autism spectrum disorders?
The Center for Disease Control and Prevention’s (CDC) Autism and Developmental Disabilities Monitoring (ADDM) Network released data in 2007 that found about 1 in 150 8-year-old children in the areas of the United States they monitor had an ASD1  For more on the numbers:  Prevalence of ASDs, from the CDC.

Autism occurs throughout the world in families of all racial, ethnic and social backgrounds. Boys are four times more likely to have autism than girls2.

The MIND Institute in California found that the number of cases of autism is on the rise. This is probably a national trend.

What causes autism?
Current research suggests that differences in the development of the brain and central nervous system cause autism. What causes these differences in brain development is not known for sure. However, a variety of factors are being investigated. These include infectious, metabolic, genetic, and environmental factors. A 1995 National Institutes of Health (NIH) working group reached a consensus that autism probably results from a genetic susceptibility that involves multiple genes. To date, genetic causes for one disorder commonly accompanied by autism (Fragile X) and one autism-spectrum disorder (Rett syndrome) have been identified and genetic "hotspots" for autism have been found. NIH research on possible genetic, infectious, immunological, and environmental causes and mechanisms of autism continues.

Do vaccines cause autism?
Research continues on vaccines and autism, and so far does not point to a connection between them.  Here are some helpful resources from the American Academy of Pediatrics:

How are autism spectrum disorders diagnosed?
Until recently, general pediatricians sometimes hesitated to screen for autism before age three. Parents often suspect a problem as early as 12 to 18 months. Go with your gut feeling, even if your pediatrician recommends you “wait and see.”  Language and “hearing” concerns are the most usual first signs.

If your child is not developing language or is losing language, seems not to “hear you" most of the time, or does not share interest in activities or objects with you, you should have your child evaluated by a specialist. Specialists can diagnose most children with ASDs by 18 months old - and the earlier the diagnosis, the sooner you can start treatment. Take your child to a developmental and behavioral pediatrician, pediatric psychiatrist, pediatric neurologist or pediatric psychologist. They are experts in diagnosing autism, and can help you figure out the best treatment plan. 

An alternative to seeing a specialist is to go to your school system.  Ask your state’s early intervention system or school system in writing for an evaluation of your child. They are required to provide it, at no cost to you. The purpose of an evaluation is to find out why your child is not meeting their developmental milestones.  A team of professionals will work with you to evaluate your child.  If they do not find a problem, and you continue to believe there is a problem, you can ask the school system to pay for an Independent Educational Evaluation (IEE).  There are strict rules about this, and they may not agree with your request.  You can also choose to have your child tested again privately, and pay for it yourself.  But check with your school district first to make sure they will accept the private test results.  By law, the school system must consider the results of the second evaluation when deciding if your child qualifies for special services.

What treatments are there for autism?
There is no single best treatment for all children with ASD.  The most important point is to start treatment as early and intensively as possible!

If you are concerned about your child's development, check out First Signs, a website with information and resources for early identification and intervention for children with developmental delays and disorders.

There is no cure for autism, but early and intensive treatment can help children with autism improve their behavior, communication and social skills. Treatment may include support and facilitation, behavior modification, educational therapy, and medicine.

Every state has an early intervention program and you will want to get your child enrolled as soon as possible. If you live in Michigan, your doctor may refer you to the Early On Program in your local school district. (Outside Michigan, you can find your state's early intervention services through the NICHCY website.) Early On (and all states' early intervention programs) offer many different services and will help set up an individualized program for your family. It is called an Individual Family Service Plan (IFSB).

It is most important to start treatment as early as possible, and make sure it involves intensive, one-on-one interaction with your child.

The National Research Council's Committee on Educational Interventions for Children with Autism has published Educating Children with Autism. It is a comprehensive report from a committee of experts from many different fields who reviewed current research and policy. They have created a "map" to guide the education of young children (birth to age eight) with autistic spectrum disorders. A section entitled "Characteristics of Effective Interventions," on page 6 of the Executive Summary of the report, states3

"The consensus across programs is generally strong concerning the need for: early entry into an intervention program; active engagement in intensive instructional programming for the equivalent of a full school day, including services that may be offered in different sites, for a minimum of 5 days a week with full-year programming; use of planned teaching opportunities, organized around relatively brief periods of time for the youngest children (e.g. 15- to 20-minute intervals); sufficient amounts of adult attention in one-to-one or very small group instruction to meet individualized goals. Overall, effective programs are more similar than different in terms of levels of organization, staffing, ongoing monitoring, and the use of certain techniques, such as discrete trial, incidental learning, and structured teaching periods. However, there are real differences in philosophy and practice that provide a range of alternatives for parents and school systems."

You can go online to read the full report from the National Academy Commission on Behavioral and Social Sciences and Education, Educating Children with Autism.

Before you make decisions regarding your child’s treatment, gather information and learn as much as you can about treatment programs in your area.  Base your decision upon your child’s needs.  The National Institute of Mental Health offers a list of questions parents can ask when making these important decisions. 

What kinds of intensive, interaction-based therapies are available?
While we do not endorse any particular interaction-based treatment program, we want you to be aware of some of the options. Some of the treatment programs that focus on working intensively and one-on-one with children are:

What about alternative treatments?
You may hear about new or alternative treatments that people are talking about.  You may also read online about treatments that claim to “cure” autism.  Before starting your child on one of these, talk about it with your child's doctor or health care provider. Many "treatments" that are marketed to parents of children with autism are very expensive, may harm you child, and are not based on sound research. Beware of treatments that claim to have a miracle "cure" for autism.

Do not let alternative or complementary treatments infringe in any way on intensive, behaviorally structured treatment programs, such as those described in the section above. We know beyond a doubt that intensive, active engagement in a therapeutic program helps young children on the autism spectrum develop skills.

What is special education?
Special education means “educational programming designed specifically for the individual.”  If your school-aged child qualifies for special education, they will have an Individualized Education Program (IEP) designed just for them. 

What happens as my child grows up into an adult?
Transition planning is planning to prepare your child to lead a rewarding life as an adult.  As your child gets closer to adulthood, they will need an IEP transition plan.  Transition planning begins at age 14.  It is part of the IEP every year after that.  At age 16, planning will begin for how your child will transition from school into the community.  The goal is for your child to become as independent as possible. Your child should take part in the planning, because their input will help make the plan more successful.  For a thorough discussion (28 pages when printed) of the transition plan, see Transition Planning: A Team Effort , from NICHCY.  For resources on youth with intellectual disabilities attending college, visit the ThinkCollege website.

What do I need to know about the laws that have to do with early intervention and special education?  What are our rights?

What are some tips for parenting kids with autism?
Pay attention to your child's environment and routine:

When you talk to your child:

To help your child improve their behavior:

Always remember to show love and caring for your child.

My child was just diagnosed. Where do we start?

Other good starting points for parents of a newly diagnosed child:

How can I get more information, help and support?

Related topics on YourChild:

Additional Information:





Written and compiled by Kyla Boyse, R.N.  Reviewed by Judith Coucouvanis, MA, APRN, BC.

Updated December 2008

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