The American Psychiatric Association (APA) has revised its diagnostic manual, known as Diagnostic and Statistical Manual (DSM). On this page, we answer questions about some of the changes relating to the diagnosis of autism and Asperger syndrome.

What are the changes?

The following changes have been made.

  • The terms used in DSM-IV are 'autistic disorder', 'Asperger’s disorder', 'childhood disintegrative disorder' and 'PDD-NOS (pervasive developmental disorder not otherwise specified)'. The revisions to DSM-5 mean that when people go for a diagnosis in the future, instead of receiving a diagnosis of one of these disorders, they would be given a diagnosis of 'autism spectrum disorder (ASD)'.
  • The previous use of three areas of impairment has been reduced to two main areas: 
    • social communication and interaction
    • restricted, repetitive patterns of behaviour, interests, or activities.
  • Sensory behaviours are included in the criteria for the first time, under the 'restricted, repetitive patterns of behaviours' descriptors.
  • The emphasis during diagnosis will change from giving a name to the condition to identifying all the needs someone has and how these affect their life.
  • 'Dimensional elements' have been introduced which give an indication of how much someone’s condition affects them. This will help to identify how much support and in what areas of function an individual needs.
  • A new condition called 'social communication disorder' has been added.

Why are these changes happening?

Diagnostic criteria are revised periodically by a team of experts, taking into account the most up-to-date research. The last change to the DSM was in 2000, and before that in 1994.

The changes are part of wider changes to the DSM. These include changing the way conditions are classified; developing 'dimensional elements' to diagnostic criteria for all conditions to help give an indication of severity; and reducing the number of 'not otherwise specified' diagnoses (such as pervasive developmental disorder not otherwise specified, or PDD-NOS).

The people involved in making the changes felt that there was not enough evidence to show a definite distinction between Asperger syndrome and high-functioning autism spectrum disorder. They have incorporated both of these terms (and others including childhood disintegrative disorder and PDD-NOS) into the overall category of 'autism spectrum disorder'.

In the future it may be possible to give even more specific diagnostic details as research continues into whether there are different types of autism and what these might be.

How long have autism and Asperger syndrome been in the DSM?

Autism was first included as a separate category in DSM-3 in 1980 when it was called 'infantile autism'. This was later changed to 'autistic disorder' in 1987. Asperger’s disorder (syndrome) was added to DSM-4 in 1994.

What research are the changes based on?

Visit the DSM website.

Where can I find out more about the changes?

Visit the DSM website's frequently asked questions

What will happen to the existing theory of a 'triad of impairments'?

The 'triad of impairments' is a description of the way we understand autism to affect an individual. The theory has not changed and people can vary widely in how these impairments are manifested. DSM-5 does not mean that this description has changed.

Why have social and communication issues been put together as one category?

In reality, it is very difficult to separate social and communication difficulties from each other, so it makes sense for them to become one category.

What do the changes mean in practice?

For people in the UK, if you have already got a diagnosis, these changes will not affect it.

What are ‘specifiers’ and why have they been included?

Specifiers have been included to help with describing the difficulties of the individual as a whole person, for autism spectrum disorder the specifiers include the following:

  • with or without accompanying intellectual impairment
  • with or without accompanying language impairment
  • associated with known medical or genetic condition or environmental factor
  • associated with another neurodevelopmental, mental, or behavioural disorder
  • with catatonia
  • onset (eg with regression) is to be described.

Will DSM-5 apply in the UK?

The DSM is very influential, although the main set of criteria used in the UK is the World Health Organisation’s International Classification of Diseases (ICD).

Using DSM-5 criteria, how many people that were previously diagnosed with some form of autism now fall under the ASD umbrella?

There have been some research studies testing the new criteria and more are underway. The results we are aware of seem to show no significant difference in the diagnosis levels with the new criteria.

Does The National Autistic Society agree with the new categorisation?

The National Autistic Society welcomes the overall approach to streamline diagnostic criteria and make them simpler, to develop dimensional measures of severity and recognise the range of full health problems someone is experiencing, as well as any other factors that impact on their diagnosis.

How do the changes help?

Overall, we believe that the changes to the diagnostic criteria are helpful. They are clearer and simpler than the previous DSM-IV criteria.

Including sensory behaviours in the criteria is useful, as many people with autism have sensory issues which affect them on a day-to-day basis. The emphasis on identifying the full range of difficulties that an individual has is also valuable.

Why have they included hypo- and hyper-sensitivity?

Sensory behaviours were part of the criteria in the DSM-III so this has reinstated them. Including sensory behaviours in the criteria is very useful, as many people with autism have sensory issues which affect them on a day-to-day basis. The emphasis on identifying the full range of difficulties that an individual has during the diagnosis process is also really valuable.

What is social communication disorder?

The APA has created a new diagnosis of social communication disorder. This would be given where someone exhibits the social communication and interaction aspects of an autism spectrum disorder diagnosis, but does not show restricted, repetitive patterns of behaviour, interests or activities. 

It is characterised by difficulties with verbal and non-verbal communication that cannot be explained by low cognitive ability. It includes difficulty in learning and using spoken and written language as well as inappropriate responses in conversation. The disorder limits effective communication, social relationships, academic achievement, or occupational performance.

What does The National Autistic Society think about social communication disorder?

From our experience of assessing people with social and communication disorders, we believe that communication problems are rarely the basis of difficulties with social interaction, but communication problems are often rooted in difficulties with social communication and interaction. Moreover, our assessments suggest that in fact these people usually do have restricted or repetitive behaviours and interests, but have been able to mask them, particularly where someone is more able intellectually.   

Therefore, though social communication disorder is not part of the autism spectrum, we believe that it is likely that this group could be a sub-group of people on the autism spectrum. When the aim of DSM-5 is to avoid having autism sub-groups, we do not believe it is helpful to have created this additional diagnosis of social communication disorder.

What will happen to someone who currently has a diagnosis of Asperger syndrome?

If you currently have a diagnosis of Asperger syndrome or Asperger disorder in the UK, this will not change.

In future, under DSM-5, people would get a diagnosis of 'autism spectrum disorder' rather than any of the current DSM diagnostic terms, which include 'autistic disorder', 'Asperger disorder' and 'PDD-NOS'. However, most diagnoses in the UK are based on the International Classification of Diseases (ICD), published by the World Health Organisation, or other criteria, such as those developed by Professor Christopher Gillberg.

The professionals who developed DSM-5 have suggested that the term 'Asperger’s' might still be used colloquially by diagnosticians; for example, for a diagnosis of autism spectrum disorder with similarities to Asperger syndrome.

Many people identify closely with the term Asperger syndrome and will continue to use it in everyday language. 

What will happen to those still waiting for a diagnosis?

The DSM is very influential, although the main set of criteria used in the UK is the World Health Organisation’s International Classification of Diseases (ICD).

Will this mean that fewer people will be diagnosed with autism spectrum disorder, or that people with Asperger syndrome won't be able to get a diagnosis in future?

In a study published in October 2012, the case records of 4,453 children previously diagnosed with an autism spectrum disorder using DSM-4 system were reviewed. In addition, the records of 690 children with other conditions, such as language disorder, were reviewed. Based on these records, the study's authors determined how proposed DSM-5 criteria identified children with an autism spectrum disorder and excluded those with other disorders.

The authors found that using the proposed new criteria, fewer children who did not have ASD were incorrectly diagnosed than when using the old DSM-4 criteria. The DSM-5 criteria also identified 91% of those diagnosed under the DSM-4 system. The children who would have lost their diagnosis under the new criteria did so mainly because their social impairments were not severe enough to meet DSM-5 criteria.

The report did not include adults, and it remains unclear how the proposed changes will affect them.

The study was published in the American Journal of Psychiatry: Application of DSM-5 Criteria for Autism Spectrum Disorder to Three Samples of Children With DSM-IV Diagnoses of Pervasive Developmental Disorders by Marisela Huerta PhD, Somer L. Bishop PhD, Amie Duncan PhD, Vanessa Hus MSc and Catherine Lord PhD.

You can read the abstract here

Diagnoses should always be based on a clinical decision about whether someone has an impairment which has a disabling effect on their daily life. Diagnoses will be given where symptoms cause impairment to everyday functioning. We believe that most people with Asperger syndrome or high-functioning autism should continue to meet the diagnostic criteria for autism spectrum disorder.

How will the process of diagnosis change?

The DSM criteria are medically-based and a diagnosis is given when 'symptoms together limit and impair everyday functioning'. The criteria create the foundation for diagnostic tools such as the DISCO (Diagnostic Interview for Social and Communication Disorders), the ADI (Autism Diagnostic Interview), and the ADOS (Autism Diagnostic Observation Schedule). These and other tools are used to collect information in order to decide whether someone is on the autism spectrum or not. Therefore, the criteria form the basis for the diagnosis, but the individual clinician’s judgement is crucial.

Now that the new criteria have been published, the various different diagnostic tools will be revised. A research paper looking at diagnosis using the DISCO based upon the DSM 5 criteria has been published The results showed that using the appropriate techniques, the DSM-5 criteria correctly identified people who should receive a diagnosis of ASD across age and ability. In particular, the researchers found that individuals with high ability or high-functioning autism diagnosed by the previous DSM-IV description were unlikely to be missed with the new DSM-5 ASD description. 

Article reference: "Diagnosing autism spectrum disorder: who will get a DSM-5 diagnosis?", Kent, R., Carrington, S., Le Couteur, A., Gould, J., Wing, L. & Leekam, S. (2013). Journal of Child Psychology and Psychiatry. Published Online: May 2013 [DOI:10.1111/jcpp.12085]

It will be important for those who make diagnoses to have training so that they understand the meaning of the revised criteria, and can identify all the ways in which an autism spectrum disorder may affect someone (including the less obvious ways).

Will the changes mean that people with autism lose their benefits?

Diagnoses that are made using the DSM criteria should always be based on a clinical decision about whether someone has an impairment that has a disabling effect on their daily life. If someone gets a diagnosis of an autism spectrum disorder, it is likely to mean that they will benefit from support or services. 
However, people who receive a diagnosis are not automatically eligible for support, services or benefits. Decisions about support and services are generally made by professionals in a person's local authority area.

What does this mean for the forthcoming ICD-11 revision? Will it follow suit?

DSM is an American publication. Most diagnoses in the UK are based on the International Classification of Diseases (ICD), published by the World Health Organisation.

The current ICD (ICD-10) is virtually the same as DSM-4. The next version of the International Classification of Diseases (ICD-11) is due to be published in 2015. The World Health Organisation will consider the changes made to DSM-5 and have said that the aim is to align the ICD with the DSM as closely as possible, but their descriptions are often slightly different. For example, the diagnostic names in ICD-10 are different to those in DSM-IV. 

At present, we are not aware of any plans to change the label of Asperger syndrome in the new edition of ICD though some professionals think it likely that the ICD-11 will follow the DSM-5 in this particular area.

For more answers to questions please see the replay of the live web chat we held with Professor Gillian Baird.