Diagnosing Autism Spectrum Disorders

An early diagnosis of autism spectrum disorder is important so that earlier needed interventions can begin, however, there are still many concerns about “labeling” a young child with autism spectrum disorder. There is a lot of evidence that indicates intensive early intervention in optimal educational settings for at least 2 years during the preschool years is very effective in improving outcomes in most young children with autism spectrum disorder.

Behavioral characteristics are the first clues clinicians use to make a diagnosis of autism spectrum disorder. Some of the characteristic behaviors of autism spectrum disorder are apparent in the first few months of life, or appear at any time during the early years. A diagnosis of autism spectrum disorder may be made if there are deficits in at least one of the following areas before the age of 3:

• Communication
• Socialization
• Restricted behavior

There are two stages to the diagnosis process:

1. Developmental screening during “well child” check-ups
2. A comprehensive evaluation by a multidisciplinary team

If your routine “well child” check-up does not include a developmental screening test, you should ask that it be done. As a parent or caretaker, your own observations and concerns about the child’s development will be very important in helping to evaluate your child.

Screening tools used to gather information about a child’s social and communication development within medical settings include:

• The Checklist of Autism in Toddlers (CHAT)
• The modified Checklist for Autism in Toddlers (M-CHAT)
• The Screening Tool of Autism in two-Year-Olds (STAT)
• The social communication Questionnaire (SCQ) (for children 4 years of age and older)

Other screening tools include:

• Parent responses to a questionnaire
• Combination of parent report and observation

Screening tools do not provide individual diagnosis. They serve to assess the need for referral for possible diagnosis of autism spectrum disorder. These screening methods may not always identify children with “mild” autism spectrum disorder like those with high-functioning autism or Asperger syndrome. Evaluators feel a key difference in children with autism from other children before the age of 2 include pointing and pretend play.

In the last few years screening tools devised to screen for Asperger syndrome and higher functioning autism include:

• The Autism Spectrum Screening Questionnaire (ASSQ)
• The Australian Scale for Asperger’s Syndrome
• The Childhood Asperger Syndrome Test (CAST) (the most recent)

These screening tools are reliable for identification of school-age children with Asperger syndrome or higher functioning autism. Concentration includes:

• Social and behavior impairments in children without significant language delay

The second stage of diagnosis is a comprehensive diagnostic evaluation. The comprehensive diagnostic evaluation is designed to accurately rule in or rule out an autism spectrum disorder or other developmental problem. The evaluation is usually done by a multidisciplinary team that includes:

• A psychologist
• A neurologist
• A psychiatrist
• A speech therapist
• Other professionals who diagnose children with autism spectrum disorder

Autism spectrum disorders are complex and often involve other neurological or genetic problems. A comprehensive evaluation should include neurologic and genetic assessments as well as in-depth cognitive and language testing. The measures developed specifically for diagnosing autism often include:

• Autism Diagnosis Interview-Revised (ADI-R)
• The Autism Diagnostic Observation Schedule (ADOS-G)

What is the Autism Diagnosis Interview-Revised (ADI-R)?

The Autism Diagnosis Interview-Revised is a structured interview that contains over 100 items and is done with the caregiver. This tool consists of four main parts:

• The child’s communication
• The child’s social interaction
• The child’s repetitive behaviors
• Age-of-onset symptoms

What is the ADOS-G?

This is an observational diagnostic tool that is used to “press” for socio-communicative behaviors that are often delayed, abnormal, or absent in children with autism spectrum disorder.

The Childhood Autism Rating Scale (CARS)

The Childhood Autism Rating Scale (CARS) is another screening tool professionals often use to evaluate:

• The child’s body movements
• Adaptation to change
• Listening response
• Verbal communication
• The child’s relationship to people

The Childhood Autism Rating Scale is suitable for use with children over 2 years of age. The evaluator not only observes the child, but also obtains related information from the parents. The evaluator then rates the child on a scale based on deviation from the typical behavior of children of the same age.

Other Tests

Two other tests that should be used to assess any child with a developmental delay are:

• A formal audio logic hearing evaluation
• Lead screening

Experts feel some hearing loss can occur with autism spectrum disorder; however, some children with autism spectrum disorder may be incorrectly diagnosed with hearing loss. Children who remain in the oral-motor stage for a long period of time require lead screening. A child with an autistic disorder usually has elevated blood lead levels.

The Responsibility of the Multidisciplinary Team

The multidisciplinary diagnostic team has a responsibility to thoroughly evaluate the child. They will assess the child’s unique strengths and weaknesses, and then determine a formal diagnosis. Once a diagnosis has been made the team will meet with the parents or caretakers of the child to explain the evaluation results.

Meeting with the Parents or Caregivers for a Final Diagnosis

Most parents are already aware that “something” was just not quite right with their child. Nonetheless, when the diagnosis of autism spectrum disorder is given, it can be devastating. Some parents may even go into a denial stage, and it may be difficult to focus on asking questions. One of the best opportunities the parents have to ask questions is while the evaluation team is together. The focus now should be: What further steps parents or caretakers of a child with autism spectrum disorder should take? It is to the best advantage of the parents or caretakers to learn as much as possible at this meeting. Take note of the name or names of professionals who you can contact later if you have further questions.

Source: National Institute of Mental Health

Disclaimer: *This article is not meant to diagnose, treat or cure any kind of a health problem. These statements have not been evaluated by the Food and Drug Administration. Always consult with your health care provider about any kind of a health problem and especially before beginning any kind of an exercise routine.

This article is FREE to publish with the resource box. Article written 5-2007.rce: National Institute of Mental Health