Childhood Autism Rating Scale (CARS)
Autism Diagnostic Observation Schedule (ADOS)
Autism Diagnostic Interview-Revised (ADI-R)
Checklist for Autism in Toddlers (CHAT)
Criteria from the Diagnostic and Statistical Manual of Mental Disorders—4th Edition Text Revision (DSM-IV –TR) must also be met. This manual is used universally by physicians, psychologists, psychiatrists, and others to evaluate conditions. It lists characteristics specific to autism.
Lesser known Pervasive Development Disorders are Rett’s Disorder and Childhood Disintegrative Disorder. These disorders cause severe regression after a period of typical development to the point where the child is extremely impaired.
Prevalence
Autism occurs at a rate of about 1 in every 150 persons worldwide. The prevalence of autism has dramatically increased in the past few years. It could be due to a more informed society requesting evaluations. It could be due to better tools for evaluating. It could be due to the increase in early screening of children in school programs. The reasons continue to be explored.
Although it has a biological cause, there are not medical tests to recognize the biological indicators of Autism Spectrum Disorders. Research is being done to consider genetic conditions and brain differences, as well as environmental and metabolic effects.
Disorders / Vaccinations
There are theories that ASD might be caused by MMR vaccinations, vitamin deficiencies, or food allergies. Research is not conclusive, but at this time evidence does not support these theories in large numbers of children.
Other Conditions
There are conditions where characteristics of autism are frequently present. These include Fragile X syndrome, Phenylketonuria (PKU), and Tuberous Sclerosis. For this reason, when a child is diagnosed with an Autism Spectrum Disorder, high resolution chromosomes and Fragile X testing will commonly be recommended. Sometimes lead testing will also be recommended since the effects of lead poisoning can result in characteristics of autism.
