Levels of Autism Spectrum Disorder (Complete Guide)

One of the developmental disorders that have occurred since the first 2 years of life is called autism spectrum disorder. Since autism is a spectrum disorder, levels of autism are different in each individual. In other meanings, a person can be mildly autistic, moderately autistic or severely autistic. Because autism symptoms can be seen at different levels in each individual. What is more, while every individual with autism spectrum disorder has certain core symptoms, many people also have additional associated symptoms such as intellectual or language impairments.

Therefore, autism education which is applied to each individual is different. Most children with autism have different levels of intelligence. However, regardless of the intelligence level, all children with autism have difficulty understanding their environment.

According to DSM-5, which is the Diagnostic and Statistical Manual of Mental Disorders 5th edition, there is a guideline in order to categorize autism spectrum disorder by levels. It was developed in order to help clinicians and other mental health professionals better describe individual cases of autism. These levels replaced other neurodevelopmental disorders that shared symptoms with autism.



Furthermore, there are 3 levels stated, each reflecting a different level of support that individuals with autism may need. These 3 levels reflect how much support they need, their ability to communicate and adaptation, and managing daily lives.

While the idea of autism levels of support makes logical sense, it is not always easy for experts in order to assign a level. In light of the fact that it could be subjective. Also, it is important to keep in mind that, it is possible to move from one level to another over time. Because their skills can enhance, their understanding can enhance, or their psychological problems can worsen.

Mental health professionals or any kind of experts should take two things into consideration in order to determine levels of autism. These are abilities of social communication and, restricted and repetitive behaviors.

The lower the level which means the less support individual with autism may need. For instance, an individual with level 3 needs more support that an individual with level 1. It should be kept in mind that there are not any guidelines regarding the specific type of support that individuals with autism might need.



Variations in the Level of Impairments


Each person with autism spectrum disorder is different from each other. That’s why there are variations in the level of each functional impairment in the same person. In addition, even among individuals who get diagnosed with the same level of autism, it can vary. Some dysfunctions or impairments might be more prominent in some individuals than in others.

Also, the functioning level which is assigned to a child or adult with autism spectrum disorder serves as a guide for what treatments, what interventions, and what kind of support the person needs in order to achieve the best functional outcome.

Due to the variations, even individuals with severe symptoms of autism may have extraordinary talents and skills. Nonverbal does not mean the same thing as incapable. Moreover, there are some individuals with mild symptoms who have also severe symptoms.

In addition, many individuals with autism have splinter skills, which means that they are able to do a specific task that does not generalize to other tasks. Splinter skills are the abilities that are completely real and legitimate, but very limited in scope.



Autism Spectrum Disorder Level 1: Requiring Support


According to the DSM-5, individuals on level 1 autism require support. They can live by themselves and maintain a high quality of life with little support. Usually, this support is taken in the form of behavioral therapy or other types of therapy, depends on the individual’s need. Both of these approaches can help improve social skills and communication skills. Also, behavioral therapy can help develop positive behaviors of individuals that might not come naturally.

Theory of Mind (ToM) is one of the most effective ways in order to treat level 1 autism. Both ToM and adaptive skill-based treatments target executive function, emotional regulation, cognitive flexibility, social communication skills and reduction in anxiety. These aspects are very important in the field of level 1 treatment.

Individuals with level 1 autism have noticeable impairments, communication problems and problems in socializing. They can have a conversation, however, it might be difficult to maintain a back-and-forth conversation. Some of them at this level might find it hard to reach out and make new friends.



They may have normal or above normal intelligence. Individuals with level 1 autism have normal level intelligence and in many cases, they score well above normal on IQ tests. Despite that, they may struggle with some tasks, especially those that require them to make sudden decisions or change regular routines. It is important to note that many individuals with level 1 autism are considered as gifted ones and they can excel in various areas of study.

At this level, individuals may show decreased interest in social interactions or activities. They might have difficulties initiating social interactions and communications, such as talking to a person. They are able to engage with a person but they may struggle to maintain a give-and-take of a typical conversation. Some of them who attempt to make friends are seen as odd and typically unsuccessful.

They may have difficulties to understand obvious signs of communication, for example, body language and gestures. They could have trouble adapting to changes in routine or behavior. They might have difficulties in planning and organizing. The inflexibility of behavior can cause significant interference with functioning in one or more contexts. They can find it difficult to switch between activities.



Autism Spectrum Disorder Level 2: Requiring Substantial Support


According to DSM-5, individuals with level 2 autism require substantial support. Generally, they need more support than individuals with level 1 autism. Even with support, they might have a hard time adjusting to changes in the environment around them.

There are a variety of therapies can help them. For example, sensory integration therapy helps individuals learn how to deal with sensory input. In other respect, individuals with level 2 autism tend to benefit from occupational therapy. This type of therapy helps them develop the skills that they need to complete daily tasks in order to make easier their daily routines, such as decision-making or job-related skills.

A person with level 2 autism, meaning that with moderate autism, may exhibit normal or below normal mental functioning. They may have some degree of mental retardation or they may have a normal IQ of about 100. This person with level 2 autism might find self-care tasks difficult and challenging.



The symptoms which are associated with level 2 autism include more severe lack of both verbal and nonverbal communication skills compared to level 1 autism. To put it in a different way, they have a significant lack of verbal and nonverbal communication skills. They might have an unusual or reduced response to social cues, communication or interactions. They mostly use overly simple sentences during the conversation.

Social impairments are apparent even with supports in place and limited initiation of social interactions is observed. For example, they can speak very simple, they can interact only with narrow interests, they can use nonverbal communication, and so on.

In addition to difficulties in communication, they may exhibit behavioral challenges. There could be behavior issues severe enough to be obvious to the people around them. And these behaviors could interfere with functioning in a variety of contexts. They may have difficulties coping with change to routine or surroundings. Mostly, they are not able to adapt to change. Furthermore, they may have narrow and specific interests.

Autism Spectrum Disorder Level 3: Requiring Very Substantial Support


According to DSM-5, individuals with level 3 autism require very substantial support because this is the most severe level of autism spectrum disorder. Individuals with this level of autism mostly need a caregiver who helps them in order to learn basic skills that will allow them to be successful in school, at home or at work.



Individuals with level 3 autism might need frequent and intensive therapy. These therapies focus on a variety of issues that those people can face with. Besides therapy, they may benefit from medication which treats autism specifically. There are certain drugs may help manage specific symptoms of autism or co-occurring disorders such as depression or trouble focusing.

In addition to more severe symptoms, they exhibit repetitive or restricted behaviors. Repetitive behaviors could be a physical action or speaking the same phrase. On the other hand, restrictive behaviors, which tend to distance someone from the world around them, might involve an inability to adapt to change or narrow interests in very specific topics. Most of the time, there is the inflexibility of their behaviors.

They have a highly visible lack of communication skills in terms of verbal and nonverbal. It causes severe impairments in functioning, very limited social interactions and communications. Also, these severe symptoms may cause a minimal response to social overtures from other people around them.

They may have a very limited desire in order to engage socially or participate in social interactions. It can be observed that trouble during changing behaviors. They have extreme difficulties coping with unexpected change to daily routine or environment around them. Also, great distress or difficulties could be demonstrated when the focus or attention are changed.



How Could the Levels of Autism Spectrum Disorder Be Diagnosed?


To get diagnosed as having autism, there is no medical testing, for example, blood testing, imagining test or scan test. Instead of those testings, behavioral symptoms, communication problems and family history are taken into account in order to help to rule out any potential genetic disorders or conditions.

Experts will ask a variety of questions about an individual’s daily habits and aspects of their social life. They may refer the individuals for psychological testing and in order to that they are consulted to mental health professionals, such as psychologists or psychiatrists. Diagnosis is based on the level with which the symptoms are most consistent.

It should be remembered that levels of autism spectrum disorder are not black and White, which means they are not certain. Not each individual with autism clearly fits into one level. However, they can provide a useful baseline in order to help experts come up with effective management plans to set achievable goals.

Types of Autism Tests


On average, half of the families of children with autism notice their children’s unusual behavior after 18 months of age. Also, on average 4/5 of families notice after 24 months. At this point, the autism test which is performed at an early stage has great importance in case of intervention and treatment.



Children with autism are not very well connected with the people around them. Children with autism who have difficulty speaking compared to their peers experience communication problems. Early diagnosis is of paramount importance, especially in the case of autism, which is manifested by the lack of eye contact. Due to the fact that autism has no definitive treatment. However, with the comprehensive training applied as a result of early diagnosis, the symptoms of autism are reduced by up to 70%.

The attention of families is very important for the diagnosis of autism. For example, if the child does not bawl when he/she is 12 months old, if there are no hand signals, if the child does not say a word when he/she is 16 months old, and if the child cannot speak even two words when he/she is 24 months old. So, if the parents observe those kinds of behaviors and take their children to the experts, it means that they can help to establish an early diagnosis of autism. Therefore, it should be kept in mind that parents should observe the different behaviors that exist in their children.

Some autism tests are prepared based on the symptoms of autism spectrum disorder and the characteristics of the child with autism. In the first stage, besides the tests that the parents have filled out, the experts’ opinions and evaluations are required. All behaviors of a child suspected of having autism are observed.



The Childhood Autism Rating Scale (CARS): Based on the observation of the child with autism’s behaviors. In the test which should be conducted by the experts, the skill of speaking, adaptation, body use and social relations are observed.

Modified Checklist for Autism in Toddlers (M-CHAT): A list of questions which were prepared by Simon Baron- Cohen and it applies to children up to 18 months. It is done with the participation of parents and pediatrician.

Autism Checklist: It is a test which is applied to children who are 4 years old or older, and it is a 40-question test which includes communication skills and social skills structures.

Screening Test for Two Years: Imitation, attention control, game and motor movements are observed. It is a kind of test that an autism screening test for children under 2 years of age.

Missing Part from These Autism Spectrum Disorder Levels in Terms of Support


Even these levels of autism spectrum disorder answer a lot of questions, they raise many questions as well. Now, let’s take a look at what kind of questions raised.



  • While developing these functional levels, what did the American Psychiatric Association want to say as a “support”? Did they want to say an aide, a personal care assistant, a one-to-one school aide, a job coach, a college advisor, or simply a mother?
  • Does location have importance in requiring support? Which means, in which situations do individuals with autism at various levels require support? Some individuals with autism could be fine at home, however, they could need help in school where demands are specific and intense. On the other hand, some of them can do well at school but they can need help in some settings, such as social and work.
  • Anxiety is one of the very common traits among individuals with higher functioning autism. And this can cause extreme challenges in typical settings. Where does the person fit into those levels if that individual is bright, verbal and academically capable but anxious and depresses, and thus in need of significant support in order to function in a job or in school?
  • Some individuals with autism spectrum disorder can have received sufficient therapy in order to appear close to typical when interviewed by a single adult but they have significant issues when interacting with their peers. So, what type of support may they need?

Atypical Autism


The diagnosis given to children who have symptoms of autism but do not meet enough criteria to be diagnosed is called atypical autism. Atypical autism is also called a diffuse developmental disorder, which cannot be named otherwise. It is a term which is used for children who do not have the characteristics of other groups in common developmental disorders.



Atypical autism includes difficulty in speaking, difficulty in communicating, delays or impairments in development, repetitive speeches and problems with socialization. However, these symptoms may occur at later ages or may appear to be less likely in order to prevent a full diagnosis. 

The most important feature that differentiates atypical autism from other types of autism is the ability to overcome speech and communication problems experienced by individuals with autism through early diagnosis and accurate treatment methods. The impact of early diagnosis is enormous when it comes to overcoming the problems and continuing the normal life of the individual.

Therefore, parents of children with autism should observe the movements and development of their children, be sensitive about the doctor controls and follow up with their children in a healthy way. If the child has symptoms of atypical autism, a child should be consulted by an expert immediately and the treatment process should be initiated quickly.

There is severe and widespread developmental disorder in mutual social interaction. There are disorders or stereotypes, interests and activities in the development of verbal and nonverbal communication skills. On the other hand, the diagnostic criteria for a specific diffuse developmental disorder, schizophrenia, schizotypal personality disorder or for the predisposing personality disorder are not fully met. If the observed symptoms are insufficient to make a diagnosis, the case is included in this category.



Symptoms of atypical autism can manifest itself in situations, such as problems related to language and social communication, problems in using the language for a purpose, excessive timidity, extreme shyness, excessive commitment to certain principles in daily and private life. With advanced age, the diagnosis or the level can be changed and the situation can turn into a personality trait.

Autistic symptoms may lower the strengths over time. With good education and favorable conditions, even though the situation cannot completely return to normal, it is possible to live a normal life. In this respect, early diagnosis and rapid transition to treatment are important. Atypical autism has no severe form and it is difficult to separate from mild autism. It can, therefore, be seen as part of the normal development process. Also, because of the reason, it can be included level 1 autism.

Autism affects three main areas of development in children; however, in atypical autism, only one of these main areas is diagnosed when a disorder is observed or if these main areas are less affected by autism. Moreover, this diagnosis is made when the criteria for other developmental disorders are not met.

Since children with atypical autism exhibit mild autism, in other words, exhibit level 1 autism, they are often confused with typical autism and Asperger’s syndrome. In addition, there may be similar situations and problems between personality disorders such as schizoid personality, schizotypal personality, timid personality, and atypical autism, but they are different. Such difficulties can be encountered and misdiagnosed, especially when making a diagnosis.



In typical autism, symptoms are prominent and severe. On the other hand, in atypical autism, symptoms are slightly lighter and many are more likely to be overcome in the future. Typical autism and atypical autism basically shares the same problems; however, problems and impairments are more severe and deeper in typical autism, so the level of persistence of symptoms is higher.

In atypical autism, with the exception of some mild symptoms, all other symptoms may disappear in time and leave the diagnosis place to personality disorder. Because some problems can be considered as personality traits. For example, adherence to rules, avoiding social environments, having few friends, dealing with narrow issues, not being open to change, etc.

The limited and narrow interest of individuals with atypical autism may lead them to success in their work; because they examine their subjects in depth and in detail. So this leads them to success in the area they are related to. While there is no tendency in order to establish social relationships in typical autism, there is this tendency in atypical autism; however, these individuals lack social skills.

There are some main problems of atypical autism. For instance, excessive timidity, introversion, shyness, strict adherence to rituals, limited attention, repetitive behavior, having strict principles, etc. The differences between atypical autism and typical autism are still unclear. Also, due to the fact that these unclear differences, level of support cannot be determined for certain. Debates continue at many points in this issue.



Persistence continues despite all training and treatments in typical autism; but with age progression and education, many problems can be eliminated in atypical autism. In both typical autism and atypical autism, the communication problem is close to each other.

While repetitive behaviors and other obsessions are the same in all types of autism at a young age, severe reductions in atypical autism are observed with age progression. Even if no reduction is observed, it is not disturbing and it does not appear to disturb the interaction with other people.

Limited interests are the same in both cases. Individuals with atypical autism are better in terms of self-care and academic skills than individuals with typical autism. In addition to those, psychiatric problems such as panic attacks and depression may occur.

Asperger’s Syndrome


Asperger’s syndrome is a problem that begins in childhood and complicates social interaction. The most important symptoms are excessive introversion, communication problem and skill weakness. Generally similar to autism. Just like autism, Asperger’s syndrome is a condition that is completely unknown and affects a lifetime.



It is important to keep in mind that Asperger’s syndrome is very individualized. For example, one with Asperger’s may have no problem with the routine getting interrupted, while another simply will not be able to function if something in the routine is disrupted.

Furthermore, one person with Asperger’s syndrome may have had issues with fine motor movements that caused a delay in when he/she learned to ride a bike, while another may have no interest in learning about activities or subjects other than those which that person already knows and loves.

Unlike typical autism, there is no developmental delay in language and speaking skills. The symptoms of Asperger’s syndrome are usually different from those of other autism spectrum disorders in older children. The most important feature that distinguishes Asperger’s syndrome and atypical autism are speech problems are observed in Asperger’s syndrome. In other words, children with Asperger’s syndrome have a very nice and grammatical speech since infancy.

In atypical autism, speech may improve in the following years. In other words, while speech problems are seen in the early stages, improvements in speech can be seen along with the progression of the age and the education received. Some individuals may continue to have speech problems at advanced ages.



In atypical autism, problems and impairments, such as reversing pronouns, not understanding speeches, and echolalia, are common. In individuals with Asperger syndrome, there may be incompetence and hand-eye coordination problems due to impairments in motor development, whereas hand skills are improved in atypical autism.

Those with Asperger’s syndrome are more social than those with atypical autism. They are more prone to social relations. In some tests, the verbal scores of the individuals with Asperger syndrome were high and the opposite was observed in individuals with atypical autism. While early learning how to read and write can be seen frequently in atypical autism, it is less common in Asperger syndrome.

Whereas symptoms in atypical autism are observed before the age of 3, symptoms in Asperger syndrome can be observed after 3 years of age and in some cases may be observed at later ages. In Symptoms of Asperger’s syndrome, such as normal development of language and speech, inadequate development of muscle skills, visual motor coordination problems, are accepted as a criterion for differential diagnosis of atypical autism.

Besides that information, Asperger syndrome and atypical autism are interchangeable. Especially in advanced age, it is difficult to distinguish between atypical autism and Asperger syndrome. According to some researchers, Asperger syndrome is a mild type of atypical autism. But this issue is still not clear. The exact lines that distinguish between atypical autism and Asperger syndrome have not yet been drawn. However, research in this area continues.


Recent Content