Autism Society Canada | Société canadienne de l'autisme

Screening and Assessment

Parents, family members or other caregivers of children with ASDs are usually first to notice delays in a child meeting the usual developmental milestones or differences in the ability to speak, make eye contact, play with other children or interact socially. In some high functioning individuals, ASDs may go unnoticed for years and be diagnosed only during an educational difficulty or a life crisis which puts a person in contact with professionals able to recognize the disorder. Autism and Aspergers may also go unnoticed when a person has other disabilities.

ASDs are not diagnosed based on only one factor or symptom but when a combination of specific behaviours, communication delays and/or developmental disabilities is confirmed. In North America, the DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) is used as the standard screening tool for Pervasive Developmental Disorders (PDDs). This is published by the American Psychiatric Association. In Europe and other parts of the world, the ICD-10 (International Classification of Diseases) is commonly used.

There are other diagnostic tools used to diagnose various ASDs including:

• Observation tools such as the Autism Diagnostic Observation Schedule (ADOS-G)
• The Childhood Autism Rating Scale (CARS)
• The Autism Diagnostic Interview - Revised (ADI-R)

Some of the common characteristics which are usually considered include:

• Lack of imaginative and social play
• Difficulty making friends with own age group
• Inability to initiate or sustain a conversation
• Stereotyped, repetitive, or unusual use of language
• Restricted and/or overly-intense interests
• Overly dependent on specific routines or rituals
• Preoccupied with parts of objects

Early screening and diagnosis result in earlier, and therefore more effective treatment. Screening tools such as The Checklist for Autism in Toddlers (CHAT) can be used by family doctors and pediatricians who are the first health professionals to see infants and toddlers on a regular basis. The earlier the diagnosis can be confirmed by a specialized diagnostic team, the earlier any necessary effective treatment can begin.

How are Particular ASDs Diagnosed in Children?

ASDs vary widely in severity and symptoms. An accurate diagnosis and early identification greatly improve the chances of establishing appropriate educational supports and any necessary treatments and interventions.

Autistic Disorder
The early development of children with Autistic Disorder may seem quite normal up to about the age of 18-24 months. Children with Autistic Disorder can be diagnosed by the age of 2. Evaluation will include reports from parents and professional observation of the child in various settings. In addition to the diagnostic tools described above, measures of the child's cognitive abilities, verbal abilities and adaptation behaviours will be made. If necessary, unusual behaviours will also be assessed and tests may be performed to identify any medical issues such as seizures. Depending on the severity and range of symptoms, a child diagnosed with autism may be "high functioning," severely developmentally delayed, or fall anywhere along the spectrum.

Asperger's Syndrome
People with autistic behaviours who have developed language at the normal age may be diagnosed with Asperger's Syndrome (AS). Often a child is already in school before AS is diagnosed or sometimes the person may diagnosed later in their teens or adult years. There is debate in clinical circles about whether Asperger's Syndrome and "high-functioning" autism are really distinct disorders and there is even less agreement on what are the best assessment tools for AS.

Cognitive, communication and motor skills are usually assessed and attention is paid the person's history and overall ability to function independently. Related disorders and those with similar symptoms including Tourette's Disorder, Obsessive Compulsive Disorder, Schizophrenia, Depression, ADHD and other learning disabilities must be considered as well.

ASD signs often ignored:
Misdiagnosis or a lack of diagnosis can cause serious delays in the child receiving necessary treatment for her/his complex needs.Unfortunately, parents of children with autism disorders are often erroneously told that their child is just a bit slow to develop certain skills, or that he/she has a behaviour problem, learning disability, hearing problem or is just a bit eccentric.

Pervasive Developmental Disorder - Not Otherwise Specified (PDD-NOS)
The DSM-IV states that a diagnosis of PDD-NOS is made when the strict criteria for Autistic Disorder and Asperger Syndrome are not met. The person will still have problems with social relationships, impaired communication and repetitive behaviours. Usually people with PDD-NOS have some language delays.

Diagnosis in Adulthood

Late diagnosis of Asperger Syndrome (AS) in adults is becoming more common as health professionals become more aware of AS and ASD and of learning disabilities in general. Receiving a diagnosis later in life can allow some individuals to understand their life events better and to access important educational, living, social and economic supports and accommodations that might otherwise have been unavailable to them.

Clinicians tend to see only those adults who arrive to see them in crisis, those who are having serious difficulty functioning, or those who are already diagnosed. Some young adults are diagnosed in their early 20s when normal life transitions begin to require them to be more independent and responsibilities suddenly increase. Once full-time school has ended, the new lack of routine, can be very debilitating for young adults with ASDs.

We don't know how many people go through life coping with an ASD without ever receiving a diagnosis for this disability and who therefore never have access to supports that may have made life easier for them. More on resources for adults and youth.

Prognosis

Autism is a lifelong disability. There is no known medical "cure" for autism but many of the disabling symptoms of autism are treatable. The earlier children with ASDs are able to receive appropriate evidence-based treatment and intervention, the better their prognosis. It is possible to help most people, even those with severely debilitating autism conditions, to experience significant improvements in their symptoms and in their ability to function. Some children may even improve to the point of being indistinguishable from their peers. More on treatment and intervention.

Progress in Autism
As awareness and knowledge increase, parents, families and people with ASDs are demanding better services, education, evidence-based treatments, accommodations, vocational opportunities, recreational/social programs and living supports. Targeted, accessible services will offer individuals with ASDs the best chance of improvement and adaptation to their disability, enabling them to reach their highest potential. It is frightening to think that less than a generation ago, most people with autism were placed in institutions, their symptoms thought to be "incurable." Health professionals and others were uneducated about autism and effective supports and services were simply not available. Today, increased knowledge and evidence-based treatment and support help people with ASDs learn effective coping mechanisms and strategies to compensate for their disability. Depending on factors such as age, treatment and educational opportunity, many of the symptoms of ASD can get better over time. With appropriate intervention, many children and adults can be assisted to learn and grow and many of the negative behaviours associated with ASDs can be greatly improved. Most people with ASDs will continue to struggle with some degree of difficulty with communication and social challenges throughout their lives.

With appropriate early intervention, autism-specific services, financial support, training and information, most families are now able to support their young children at home. Group homes, assisted apartment living arrangements or residential facilities also offer out of home support. [More on treatments] These days, some adults with ASDs are able to live and work independently, earn a university/college degree, hold a rewarding job, get married, etc. Others may be semi-independent and able to live in the community with support for certain aspects of day-to-day living. There will also be individuals with more severe forms of ASDs who will remain very dependent on family and on professional support throughout their lives. More on living with ASDs.

For Resources and Links: Screening, Diagnosis, Assessment please see Resources for Professionals.