A free online resource developed to support the inclusion of autistic learners in Scottish Early Learning and Childcare settings, Primary and Secondary schools.

Understanding Autism - Terminology

What language should we use to describe autism and autistic people?

It is important to explain the choice of language and terminology used in the Autism Toolbox because the complex nature of autism gives rise to a range of personal and professional perspectives. Although this means that it is not easy to find a common language that reflects the views of the various groups, what we have tried to do is reflect the diversity of the community in a positive way. 

Autism as an identity

Many different terms are used to describe autism and there is no agreement within the community of autistic people, parents and their broader support network or the wider community on the best term to use. 

Within the wider community there seems to be most consensus for the terms ‘autism’ and also ‘on the autism spectrum’. 

Within the autism community many autistic people prefer the use of the term autistic for example ‘autistic adult’ and the concept of autism spectrum disorder (ASD) has been rejected by some with autism community because of the term 'disorder'  presents the view that this is a disorder; autism represents a difference not a deficit. Select the link to view a blog which explores terminology https://dart.ed.ac.uk/autism-language

Within the education community  it is unusual to use a term which defines a diagnosis or identification before the words learner, child or young person; for example, we would not encourage the term a ‘physically or mentally disabled learner’ we would instead encourage the learner to be understood as an individual first before any differences or difficulties. For example, ‘a child with autism’, however, some people within the autistic community have requested the term autistic person. This toolbox will use the term autistic learner or autistic children.   

If the child, young person or family express a preference for a particular term, this should be respected.

The word spectrum emphasises the variation amongst autistic people, with individuals having a unique pattern of strengths and difficulties. People on the autism spectrum have a range of intellectual abilities and will present differently depending on developmental stage and sex. People on the autism spectrum will have a range of strengths and challenges and some will require a high level of need for support, while others will have more subtle difficulties that may still require support. People on the autism spectrum will also have individual differences in the range of their strengths and talents.

Two main diagnostic manuals are used in the UK as recommended in the SIGN Guidelines 145. One of these is DSM-5 and in 2013 in the latest addition it moved away from a list of subtypes of autism (such as Asperger Syndrome) to one diagnosis called autistic spectrum disorder. The other main manual used in the UK, ICD-10 is due to be updated in 2019 and is expected to be similar to the latest DSM manual.

In the past few decades a number of diagnostic labels have been used by professionals as different diagnostic manuals and tools have been used to identify if someone has autism. 

These terms  historically included Classic Autism, Kanner Autism, Asperger Syndrome and Pervasive Developmental Disorder.

Further diagnostic information can be found in the 'Assessing and Monitoring' section.

What does PDA refer to?

The term PDA was introduced in the 1980’s to describe some children and young people who presented with social and communication disorders. These individuals were thought to have more resistance to following social expectations, to be socially manipulative and to have better play skills than the majority of children and young people diagnosed with Autism, using the diagnostic criteria available at that time. 

Our understanding of the wide spectrum of Autism Spectrum Disorder (ASD) has developed considerably since the term PDA was introduced. Autism is a lifelong neuro-developmental difference meaning it is a condition that affects the development of the brain. Autism affects the way a person communicates and interacts with others, how information is processed and how the person makes sense of the world.    


Is PDA a diagnosed neurodevelopmental condition?

Within the NHS in Scotland, practitioners are guided by the Scottish Intercollegiate Guidelines Network (SIGN) to ensure practice is safe and evidence based.  Based on the SIGN guidance, a diagnosis of neurodevelopmental or mental health condition is made following adherence to two major international diagnostic classification systems Statistical Manual of Mental Disorders 5th edition (DSM 5) or International Classification of Diseases, version 10 (ICD 10).  PDA is not considered a separate condition and therefore is not included in either of these classification systems. A clinical diagnosis cannot be given in the absence of clinical criteria. 

As research and understanding of the nature of autism progresses it is increasingly recognised that what were previously thought of as distinct conditions (subgroups) actually describe manifestations of autism. Recent diagnostic criteria now includes a much broader group of people fitting the diagnosis of ASD and has have moved away from subgroups for example;

  • Asperger’s syndrome
  • Pervasive Developmental Disorder-Not Otherwise Specified (PDDNOS)
  • Semantic Pragmatic Disorder

towards a conceptualisation of autism which takes account of the profile some describe as PDA, without the need for other diagnoses. Essentially all ‘PDA’ characteristics are explained by ASD in the context of an individual whose need for predictability has not been met/ is not met.  The term ‘PDA’ placed the ‘problem’ within the child, however we now understand that there is a dynamic relationship between the individual and the environment and that avoidance of demand should be understood in the context of the physical and social environment. Establishing full understanding of the social impairment, sensory differences and inflexible thinking that lead to extreme anxiety in autism would be a better way forward.  Importantly, professionals would always wish to offer families an opportunity to discuss what has led them to feel that PDA is an appropriate way to describe their child’s presentation and should seek to support an individualised approach to supporting them that takes account of their individual circumstances. This will include understanding their needs and relevant support strategies.


The Scottish Government’s commitment to autistic people is and will continue to be framed within clinical guidelines and the international standards cited above.  The “symptoms” of PDA are described in ASD. The behaviours described as PDA are all compatible with the ASD diagnosis and further clinical diagnostic assessment is not available in the absence of inclusion in any internationally recognised classification systems.   

Further Professional Development

Select here to access the Professional Reflection and Planning Tool (Understanding Autism) for this section.

Further resources can be found in the Professional Development section.