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Autism Spectrum Disorder - ASD (Children)

2024/05/16
What Is Autism Spectrum Disorder

Autism or autism spectrum disorder (ASD) is a lifelong neuro-developmental condition. It is characterised by:

  • Persistent impairment in reciprocal social communication and social interaction
  • Restricted, repetitive patterns of behaviour, interests, or activities
  • Symptoms of ASD from early childhood and limitations or impairment in day-to-day functioning

The worldwide prevalence of ASD is estimated to be about 1%. The local prevalence rates are not known exactly but there are at least 400 new cases diagnosed annually in Singapore.

The probability of someone with ASD having a sibling with ASD is approximately 20%.

Causes Of Autism

There is no one cause of autism. Most cases of autism appear to be caused by a combination of genetic and environmental factors influencing early brain development.

Autism is not caused by a child's upbringing or social circumstances, nor is it the fault of the individual that they have autism.

So far, research has not demonstrated a link between vaccination and autism.

There are some who believe that oral supplements or special diets can help reduce behaviours associated with autism. However, these has not yet been proven with well-conducted trials, so we cannot currently comment on their safety or usefulness.

Signs And Symptoms Of Autism

A child with ASD may have one or more of the following difficulties:

  • Social communication and interaction
    A child with ASD may have trouble communicating or initiating social interactions with others and may not respond to others in an expected way. He or she may prefer to play alone and may have difficulties playing interactively with others and difficulties using non-verbal communication (e.g. gestures, pointing, eye contact).
  • Repetitive behaviours or restricted interests
    A child with ASD may have unusually intense interests (e.g. interest in car logos) or exhibit unusual repetitive hand or body movements such as hand flapping or spinning body. He or she may have limitations with imaginative or pretend play, and may engage in repetitive play or play with toys in an unusual manner (e.g. more interested in lining up objects or spinning wheels of a toy cars than rolling or moving the car). He or she has fixed routines and rituals and can be resistant to changes or transitions.
  • Unusual interest or sensitivity to sensory input
    The child may show under- or over- sensitivity to sensory aspects in their surroundings (e.g. the way things look, smell, taste, feel, or sound like).
  • Delays in social or language developmental milestones
    • Not responding to his/her name when called
    • Not looking at what caregivers look or point at
    • Not smiling back at others who smile at him/her
    • Not pointing or other gestures (e.g. nodding, shaking head, clapping, waving) by 12 months
    • Not using single words meaningfully by 18 months
    • Any loss of language or social skills at any age

ASD is a spectrum and symptoms may vary from child to child depending on various reasons such as age, developmental level, and severity.

If you have any concerns about your child’s communication, behaviour or social and play skills, or if your child has one or more of the above clinical features, you should inform a healthcare professional(s) as soon as possible, as early diagnosis and intervention is very important.

Diagnosis And Treatment Options For Autism

A full evaluation should be done by a multidisciplinary team of healthcare professionals, which may involve a paediatrician specialising in behavioural and developmental paediatrics, a child psychiatrist or psychologist, and a speech or occupational therapist. Doctors may also call for a hearing test to be performed by an audiologist to ensure that hearing loss is not the primary underlying reason for the lack of social communication and interaction.

There are several assessment tools that are available for diagnostic purposes, including the most commonly used Autism Diagnostic Observation Schedule (ADOS) and Autism Diagnostic Interview-Revised (ADI-R). These are conducted by psychologists who are trained to use them. Measures of the child’s speech and language skills and intellectual ability also help professionals plan intervention.

Having a formal diagnosis is useful because it helps people with autism and their families or school understand their difficulties and what can be done about them. It also allows people to access services and support.

Early intervention can make a big difference to many children with ASD by improving their skills and quality of life and helping them to be more independent. There are many treatment options for ASD which help improve outcomes for children.

Depending on the child’s presenting difficulties, different therapists (e.g. speech therapist, occupational therapist, psychologist) may support the development of the child’s skills in specific areas of need such as communication, social interaction, activities of daily living, and play skills. Some children may need more intensive intervention. In Singapore, these may be in the form of early intervention programmes provided by government-funded organisations or private centres.

There are no medications that treat the condition itself. However, some medications may be useful for minimising self-injurious or aggressive behaviours, associated anxiety, hyperactivity, or sleep difficulties in children with ASD.

There are many services that claim to provide complementary alternative treatments that can help children with ASD. However, these have not been proven in clinical trials and there is insufficient high quality evidence to support their use.

Depending on the child's presenting difficulties, different therapists (e.g. speech therapist, occupational therapist, psychologist) may support the development of the child's skills in specific areas of need such as communication, social interaction, activities of daily living, and play skills. Some children may need more intensive intervention. In Singapore, these may be in the form of early intervention programmes provided by government-funded organisations or private centres.

There are no medications that treat the condition itself. However, some medications may be useful for minimising self-injurious or aggressive behaviours, associated anxiety or hyperactivity, or sleep difficulties in children with ASD.

There are many services that claim to provide complementary alternative treatments that can help children with ASD. However, these have not been proven in clinical trials and there is insufficient high quality evidence to support their use.

Frequently Asked Questions About Autism Assessment

1. What is autism or autism spectrum disorder (ASD)?

2. Why did the doctor refer my child for an autism assessment?

3. At what age can autism be diagnosed?

4. How is the diagnosis of autism made? Are there any special tests the doctor can do to determine whether my child is autistic?

5. What tests will the paediatricians and specialists use in the diagnosis of ASD?

6. How is a typical autism assessment like?

7. What can I do to prepare for the autism assessment session?

8. Why is it important to make the diagnosis? Can I wait till my child is much older?

1. What is autism or autism spectrum disorder (ASD)?

ASD is a lifelong neuro-developmental condition where a child has difficulties in social communication and interaction, as well as some restricted and/or repetitive patterns of behaviour, interests or activities. These may be present in varying severity.


2. Why did the doctor refer my child for an autism assessment?

The doctor may refer your child for an autism assessment if he or she:

  • Has difficulty making friends and playing interactively with same-aged peers,
  • Has difficulties using non-verbal communication (e.g. gestures, pointing, eye contact),
  • Has some unusually intense interests (e.g. interest in car logos), unusual repetitive behaviours (e.g. hand flapping, spinning body) or fixed routines and rituals,
  • Has difficulties with imaginative play or plays with toys in unusual manner (e.g. more interested in spinning wheels of the cars or lining up cars than rolling or moving the car), and/or
  • Has unusual interest or sensitivity to sensory input (e.g., the way things look, smell, taste, feel, or sound like).

Please note that these are just some common behaviours and this list is not exhaustive.


3. At what age can autism be diagnosed?

Children can be screened for the disorder from as young as 18 months, and a diagnostic assessment can be done from 31 months. However, it is sometimes difficult to distinguish between autism and global developmental delay at a young age and each child might present differently. Your doctor will thus determine the most suitable age for your child to be assessed.

4. How is the diagnosis of autism made? Are there any special tests the doctor can do to determine whether my child is autistic?

At present, there are no biological tests that can be used to diagnose ASD, unlike certain medical conditions where a blood test or X-ray may provide exact results. Nevertheless, your doctor may recommend a blood test, genetic test, or brain scan to rule out the presence of other medical conditions that can co-occur with autism.

An autism diagnosis is based on a thorough assessment that includes a detailed developmental history from parents, observations made by your child’s therapist(s) and/or teacher(s), and direct observations by a psychologist.


5. What tests will the paediatricians and specialists use in the diagnosis of ASD?

The doctor may give out questionnaires to parents and teachers to ascertain if the child has difficulties at home or in school that maybe related to autism. A physical examination will also be performed to exclude other co-existing medical conditions.

Subsequently, a referral may be made to a psychologist to conduct testing using tools developed specifically for diagnosing ASD. The most common tools used are the Autism Diagnosis Interview-Revised (ADI-R) and Autism Diagnostic Observation Schedule (ADOS).

  • The ADI-R is a standardised, semi-structured clinical interview for caregivers. The interview takes 2 to 3 hours and it focuses on behaviours in three areas: quality of social interaction; communication and language; and repetitive, restricted and stereotyped interests and behaviour.
  • The ADOS is a semi-structured, clinic-based play observation. The observation requires 40 minutes to an hour. It involves activities like playing with toys, looking at pictures, and snack time. The activities assess a child’s social communication, social interaction and play or imaginative use of materials.


6. How is a typical autism assessment like?

A typical autism assessment requires a total of 3 to 4 hours, and is conducted over about three sessions. The assessment sessions will be scheduled based on the availability of the psychologist and parents.


7. What can I do to prepare before the autism assessment session?

For sessions with the child:

  • Allow the child to have plenty of rest the night before.
  • Have meals on the day of the test.
  • Talk to your child about where he/she will be going, who he/she will meet, and what he/she may do.
  • Reach 10 to 15 minutes before the time of test to let your child get used to the clinic environment.
  • Please reschedule the session if your child is unwell or feeling tired.

For parent interviews:

  • Take leave or ensure you will not be interrupted during the time of the interview.
  • Review your child’s past medical records or videos to note his/her speech and motor developmental milestones. It will be very helpful to recall and/or observe your child’s interactions with familiar and unfamiliar adults and children. Do note any unusual behaviours and interests (e.g. spinning body, lining up objects etc) and how long these behaviours have lasted.
  • If your child is above 5 years old, recall his/ her behaviours at the particular period when he/she was 4 to 5 years old.

8. Why is it important to make the diagnosis? Can I wait till my child is much older?

It is important to identify children with possible ASD early so that they can receive appropriate intervention and support services that are targeted to address their learning needs. Research indicates that early intervention can improve children’s developmental outcomes, including improved language, cognitive, social and motor skills.

A diagnosis is also helpful for school-going children. It allows for schools to allocate resources (e.g. allied educator or special programmes) to support them. Exam accommodations and leniency in marking of some tests may also be applied for should it be deemed necessary by the psychologist and/or school.

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