LD Network

How ASD Gets Diagnosed?

There are no medical tests such as blood work and brain scan to determine ASD. A medical diagnosis can be made by a psychologist, developmental pediatrician, or other specialized physician based on an assessment of symptoms and diagnostic tests.

Table of Contents

How to Get Diagnosed?

Autism is not an illness. Instead, it is a diagnosis that an individual’s brain works in a way different than most people. It is something you’re born with and not the individual’s fault or the consequence of something they did. Since it is not an illness, it has no “cure.” Some autistic people require little to no support at all. However, some things can be done to support an individual diagnosed as autistic if they need help.

Autism spectrum disorder (ASD) includes autistic disorder, Asperger’s syndrome, childhood disintegrative disorder, and Pervasive Developmental Disorder-Not Otherwise Specified (PDD-NOS or PDD for short).

To be diagnosed, the individual must exhibit difficulties in two areas that severely impact everyday life: social communication and interaction (poor social-emotional relations and reciprocity) and restricted, repetitive behaviour patterns.

Social Communication and Interaction Issues

Examples of social communication and interaction issues related to ASD include deficits in empathy, speech, body language, facial expression and eye contact, difficulties in social interactions, and making friends. For a child, this can be noticed as the child:

  • Avoids eye contact.
  • Is not responding to name 9 months after birth.
  • Does not show facial expressions (e.g., happy, sad, angry, surprised) at 9 months.
  • After 12 months old, he does not play simple interactive games.
  • Do not share interests with others after clocking 15 months.
  • Is not able to look at or point at anything you point to at a year and 6 months.
  • Has clocked 2 years but does not notice when others are hurt or sad.
  • He is not able to pretend in play at 2 years and 6 months old.
  • He is not showing enough interest in relating with peers.
  • Finds it difficult to understand other people’s feelings or talk about their own feelings at 3 years or older.

Restricted or Repetitive behaviours or Interests

Repetitive behaviour patterns indicative of ASD include an insistence on rigid routines and certain places, fixation on specific topics, sensory hyper- and hypo- sensitivities such as sensitivity to noise or light, and high pain threshold. Specifically, these behaviours can be exhibited as the child:

  • Lines up toys and gets upset when the order is changed
  • Repeats words or phrases over and over
  • Plays with things the same way every time
  • Is obsessively focused on parts of objects
  • Gets upset by minor changes
  • Has obsessive interests
  • Must follow certain routines
  • Gets upset when moved to an unfamiliar environment

rocks body, or spins self in circles

  • Reacts strangely to sensory stimulus: sounds, tastes, smells, sights, or touch

Other symptoms which accompany autism include

  • sleep disorders
  • Unusual eating and sleeping habits
  • Delayed language skills
  • Delayed movement skills
  • Unusual mood or emotional reaction
  • Seizures or epilepsy
  • gastrointestinal (GI) issues
  • Anxiety, stress, excessive worry, or depression
  • Attention deficit (hyperactivity) disorders
  • Impulsive behaviour

Some people might experience these symptoms without ASD. Although, these difficulties make life very challenging for people with ASD.

Despite all these symptoms, autistic people can live a full life. Like everyone, they have things they’re good at as well as things they struggle with. Some people on the autistic spectrum have better aptitude in specific areas like mathematics and music than the average person.

It’s not clear what causes autism or if it has a cause. Vaccines, bad parenting, diet, or infection are not known to be the cause of autism. Also, autism cannot spread from person to person.

Talk to someone for advice

The signs and symptoms of ASD can be identified through early surveillance and screening. Surveillance is an ongoing process of observing a child’s skills and abilities while interacting with parents, caregivers, and peers. This helps parents and providers identify when there might be a concern and if more screening is needed. 

Screening happens when a parent or provider completes a checklist specifically designed to identify problems that need further evaluation. In addition to general developmental screening, autism-specific screening should occur at the 18-, 24- and 30-month visits and whenever a concern is expressed.

The following are some of the helpful screening tools that might be useful in helping you identify ASD symptoms in you or your child:

  • Ages and Stages Questionnaires
  • Communication and Symbolic Behaviour Scales
  • Parents’ Evaluation of Developmental Status (PEDS)
  • Modified Checklist for Autism in Toddlers (MCHAT)
  • Screening Tool for Autism in Toddlers and Young Children (STAT)

Note that you do not need to use all these tools for the screening. These screening tools are guides and do not provide conclusive evidence of developmental delays nor result in diagnoses. They are rather tools to help you determine if a further thorough assessment is needed.

If your child or someone around you is showing signs of autism, you need to talk to an expert about it. You may want to speak to a health professional first and ask them for references to autism specialists they know and trust.

People you could speak to include:

  • A general practitioner
  • A paediatrician
  • A psychologist or psychiatrist
  • An occupational therapist or speech pathologist
  • The staff of special education needs at your child’s school

Only an autism specialist should conduct an autism assessment. Once a health professional has referred you, you may have to wait for a few months to get an appointment.

How to find Where to go for an assessment

To prepare for the assessment, kindly note the following.


  • Bring along a list of autism signs you think you or your child have. See the lists above.
  • Find out from people who know you or your child very well if they have noticed any of the signs listed.
  • Come along with writing materials so you can take notes
  • Bring someone close to you along if you think it would help (this is not necessary)


  • Show family and friends your list of signs before showing them the general list. Your list may bias their assessment.
  • Talk too much about other things apart from autism.

Have an Autism Assessment

An autism assessment is a process where a team of autism specialists examines you or your child for autism.

Getting an Assessment

Once you get a reference for an assessment team, book an appointment for your initial visit. The assessment team will inform you of the things you need to do to prepare for the assessment. This may include filling questionnaires, getting reports from the school or workplace, talking to friends and peers, etc. The autism assessment will happen over one or more appointments with a team of various professionals. The assessment may also take place over several months.

What to do while you wait for an Assessment

In case your child or yourself needs support at home, school, or work, you can start looking for the needed assistance while you wait for the assessment. You can:

  • ask for the suggestion of the assessment team on good support groups
  • get a local support group using the Autism Service Directory
  • talk to special educational needs staff or teachers at your child’s school
  • talk with your human resource manager at work
  • speak to the student support services university or college

What Happens During an Autism Assessment

During an autism assessment, the assessment team will speak with you and your family to find out about the different aspects of your life, so they can know you better. They will ask different questions.

The questions or conversation that will take place with the assessment team for children would be different from that of the adult.

For children

During the autism assessment for children, the assessment team will:

  • Observe how you and your child interact. They will also watch how your child plays.
  • Ask about any problems your child is having
  • Ask about your child’s development process like when he started talking
  • Discuss with people who know you or your child well, including family, friends, teachers, and doctors
  • Read any reports sent by your family doctor or the school
  • Visit your child’s school to observe how they cope in class and what they do at break time.

For adults

During the autism assessment for adults, the assessment team will:

  • Request that you fill a questionnaire so they get to know you better and any problems you might have.
  • Talk to someone who knew your childhood so they can get the needed information about your childhood.
  • Read the reports from the GP about your medical history or other health problems you might have

Getting the Result

The assessment result can be given to you by the team physically, by post, or online.

The report of the assessment will tell you:

  • if you or your child meet the criteria for ASD (Autism Spectrum Diagnosis).
  • Which areas you or your child might need support with. This includes communication, social interaction, behaviours or sensitivity to pain, sounds, colours, and lights.
  • What aspects are your strong points (areas where you are good at).
  • If you do not understand the report, ask the assessment team to explain it, its implications, and your next line of action.

If You Do Not Agree With The Result

Diagnosis of ASD in both adults and young people can be contradictory and complex, even among professionals. It is therefore not strange if you disagree with the result given to you.

The following factors have been found to correlate with greater differences between results and family opinion:

  • Higher intelligence
  • Better “adaptive” or living skills
  • More behaviour problems

The report may say:

  • You or your child do not have ASD.
  • It would be best if you were patient until your child is older to get another assessment done because the signs of autism are not yet clear.
  • the diagnosis is a learning disability or some other diagnosis you disagree with

Find out reasons for the diagnosis the assessment team gave.

If you still doubt the diagnosis, you can request that the GP refer you to another assessment team for a second opinion.


Autism is not a disease, but its diagnosis can help those affected get the help they need. Early diagnosis goes a long way in the management of the disorder. Autism diagnosis involves many specialists, professionals, and tests. People waiting for a diagnosis can start some therapies.