Diagnosing Autism Spectrum Disorder in Children

Autism spectrum disorder is a group of complex neurological and developmental disorders that affect brain development and cause social, communication, and behavioral challenges.

People with the condition have difficulty with social interactions and verbal and nonverbal communication. They may also exhibit repetitive behaviors or restricted interests. Signs of autism spectrum disorder begin to appear during early childhood and typically last throughout a person’s life.

Children with autism spectrum disorder develop social and communication skills in different ways and at different ages than their peers. Some babies become overly focused on certain objects, rarely making eye contact. They may fail to engage in typical back-and-forth play and babbling with their parents. Other children may develop typically but then show a regression in social, language, or other skills. 

A young child with autism spectrum disorder may not smile in social situations, have poor social interactions, prefer to be alone, and not make gestures, such as pointing or showing objects. Imaginative play may be minimal or nonexistent.

A Spectrum Disorder

Autism is considered a spectrum disorder, meaning symptoms and variations occur along a continuum. Some children, for instance, have average or above average cognitive and language abilities (previously, they may have been described as having Asperger syndrome).

Other children with autism spectrum disorder are more severely impaired. These impairments may include speech delay, problems with eye contact, limited facial expression, a restricted range of interests, and preoccupation with unusual things, such as the train schedule or the location of every police station in a city.

The learning, thinking, and problem-solving abilities of people with autism spectrum disorder range from advanced to severely challenged. Some people with the condition need significant daily help, whereas others need less assistance.

Symptoms can fall anywhere on this spectrum. The common difficulties people with autism spectrum disorder share are problems with social and communication skills and restrictive or repetitive behaviors.

People with autism spectrum disorder may communicate, interact, behave, and learn in ways that are different from most other people. For example, a person with the disorder may have difficulty using and interpreting nonverbal behaviors. This may include problems with facial expressions and body language as well as verbal conventions, such as taking turns while having a conversation.

Getting the Most Accurate Diagnosis

Early diagnosis is important to help families, caregivers, and schools understand the needs of a child with autism spectrum disorder. The child and adolescent psychologists and psychiatrists at NYU Langone’s Child Study Center offer expert diagnostic evaluations for children as young as 12 months old through adulthood. 

A comprehensive evaluation for autism spectrum disorder for young children includes several visits with our clinical and developmental child psychologists. These experts specialize in evaluating toddlers and young children suspected of having autism spectrum disorder or other communication disorders.

Evaluations are tailored to the needs of each family and include a thorough review of the child’s behavior and development. Our experts gain information about the child’s behavior and developmental milestones through direct observation, interviews with parents, speech and language evaluations, and cognitive assessments. The evaluation is play-based and tests the child's understanding of words, as well as social communication skills, such as imitation, reciprocity, and initiation. 

At the end of the evaluation, parents meet with our specialists and are given detailed recommendations and an in-depth report. Each evaluation also includes a consultation with an experienced social worker, who reviews the experts’ recommendations. The social worker then provides families and children with the appropriate therapeutic and educational referrals.

Diagnostic Interviews

Specialists use standardized assessments during evaluations to help assess autism spectrum disorder in children. The Autism Diagnostic Observation Schedule™ (ADOS™-2) is a standardized assessment of communication, social interaction, play, and restricted and repetitive behaviors in children. During an ADOS™-2 assessment, a specialist interacts directly with the child in social and play activities. 

For example, the specialist sees whether the child responds to his or her name and how he or she performs in imaginary play. The specialist observes verbal and nonverbal communication and looks for specific characteristics that are hallmarks of autism spectrum disorder, such as difficulty with age-appropriate social interaction, circumscribed interests, or repetitive speech or behavior. 

Our experts also use the Autism Diagnostic Interview™, Revised (ADI™-R), a structured interview conducted with parents that focuses on a child’s behavior in three main areas: qualities of reciprocal social interaction, communication and language, and restricted and repetitive interests and behaviors.

The ADI™-R asks general and specific questions about a child’s current and past behavior. Verbal and nonverbal communication, play and social skills, and restricted interests and repetitive behaviors are scored.

Neuropsychological Testing

A neuropsychological evaluation involves cognitive and achievement testing, as well as further specialized testing of memory, attention, and executive function, to pinpoint a child's abilities and deficits in learning and communicating.

During this evaluation, the child’s parents provide our specialists with a comprehensive history of the child’s behavior and symptoms since birth. Our experts may also gather information from teachers or directly observe the child in the classroom. 

The results of this process yield important information concerning intellectual ability and strengths. This includes information about the child’s: ability to use language appropriately in social circumstances; attention and executive function, which includes details about organizational skills and decision making; visual and perception skills; motor coordination; social knowledge; and recognition of faces and facial expression, learning, and memory.

Hearing and Vision Screening 

Doctors may also seek to rule out hearing and vision problems that could be causing symptoms that are similar to those of autism spectrum disorder. A doctor may test a child’s hearing and vision with simple auditory and visual exams.

Genetic Testing 

Changes, or mutations, in a person’s genes can be associated with the development of autism spectrum disorder. In fact, it’s believed that some genetic mutations may be the sole cause of this condition.

In most instances, however, autism spectrum disorder appears to be the result of a combination of gene mutations and environmental factors. These environmental factors, most of which have yet to be identified, are believed to influence early brain development. 

Geneticists at NYU Langone’s Clinical Genetic Services offer genetic testing for children with autism spectrum disorder. This can help to provide physical evidence of gene mutations associated with the condition, which the doctor can then use to make a diagnosis. A detailed family history and clinical examination help our geneticists to select the most appropriate tests.

Chromosome analysis and microarray are usually performed initially. These look for additional or missing DNA material and can reveal the genetic cause of autism spectrum disorder in a small percentage of children. These tests involve taking a blood sample from the child with the parents’ written consent and having geneticists and genetic counselors interpret the results.

If the results of these tests are normal, additional genetic evaluations can determine if a child has genes associated with autism spectrum disorder, or if another condition may be causing the child’s symptoms. For example, fragile X syndrome, which causes developmental and learning problems as well as autism spectrum–like behaviors, can be identified with a specific DNA test.

Although there is a genetic component to autism spectrum disorder, there is no genetic test to determine whether or not a child has the condition. Genetic tests, however, can determine the genetic changes that cause autism. These genetic changes can be particular to the child—new mutations are a common cause of autism—or hereditary.

Genetic changes associated with autism sometimes cause other medical issues that require care or treatment. These may include microdeletion syndromes, which are associated with cardiovascular abnormalities and may not be diagnosed or treated unless they are identified by genetic testing. Specialists at NYU Langone’s Clinical Genetic Services coordinates care for people with medical issues such as these.

The specialists at the Child Study Center offer follow-up care to children diagnosed with autism spectrum disorder. Our experts use the results of this comprehensive evaluation to craft an individualized treatment plan for your child.

They can also teach you how to use evidence-based practices, such as behavioral therapies, at home, to complement the therapy and treatment your child receives at NYU Langone.