Abstract

Pathological demand avoidance (PDA) is a proposed subtype of autism characterized by an avoidance of demand-framed requests by an individual. It was proposed in 1980 by the UK child psychologist Elizabeth Newson. The Elizabeth Newson Centre in Nottingham, England carries out assessments for the NHS, local authorities and private patients around autism spectrum disorder, which include, but are not exclusively PDA.

PDA behaviours are consistent with autism, but have differences from other autism subtypes diagnoses. It is not recognised by either the DSM-5 or the .

Recognition

Pathological Demand Avoidance is not recognised by the DSM-5 or ICD-10, the two main classification systems for mental disorder.

To be recognized a sufficient amount of consensus and clinical history needs to be present, and as a newly proposed condition PDA had not met the standard of evidence required at the time of recent revisions. In April 2014 the UK Minister of State for Care and Support Norman Lamb stated that the Department of Health, "In the course of the development of the National Institute for Health and Care Excellence (NICE) clinical guideline on the treatment of autism in children and young people (CG128), the developers looked at differential diagnoses for autism. In this, they did consider PDA, identifying it as a particular subgroup of autism that could also be described as oppositional defiant disorder (ODD). The guidance recommends that consideration should be given to differential diagnoses for autism (including ODD) and whether specific assessments are needed to help interpret the autism history and observations. However, due to the lack of evidence and the fact that the syndrome is not recognised within the DSM or ICD classifications, NICE was unable to develop specific recommendations on the assessment and treatment of PDA."

So the National Institute for Health and Care Excellence (which provides guidelines on best practice for UK clinicians) makes no mention of PDA in its guidelines for diagnosis of autism either in children or adults.

Criticisms

Although PDA is described as a subtype of autism, some of the proposed diagnostic criteria appear to contradict the definitions of autistic spectrum disorder. For example, one criterion for PDA is "Comfortable in role play and pretending" but the DSM-5 criteria for ASD includes "difficulties in sharing imaginative play", "inflexible adherence to routines", "rigid thinking patterns". Defenders of PDA claim this difference (amongst several others) is a subtype difference within ASD and does not invalidate the existence of PDA.

Garralda (2003) in responding to a paper by Newsom suggests that a number of case studies described by Newsom could be explained as a child who has both a developmental disorder and a coexisting mental disorder. She also suggests that a number of the proposed features could be difficult to reliably quantify (e.g. sense of identity, pride, shame).

Proposed diagnostic criteria

The defining criteria developed by Newson include:

1. Passive early history in the first year, avoiding ordinary demands and missing milestones

2. Continuing to avoid demands, panic attacks if demands are escalated

3. Surface sociability, but apparent lack of sense of social identity

4. Lability of mood and impulsive

5. Comfortable in role play and pretending

6. Language delay, seemingly the result of passivity

7. Obsessive behavior

8. Neurological signs (awkwardness, similar to autism spectrum disorders)

The Diagnostic Interview for Social and Communication Disorders (DISCO) was developed for use at The Centre for Social and Communication Disorders, by Lorna Wing and Judith Gould, as both a clinical and a research instrument for use with children and adults of any age. The questionnaire has 17 recognized markers for PDA within it.

Suggested interventions

Christie suggests a number of interventions that may be helpful, such as,

- the child having a keyworker in school

- making use of a "den" or "safe haven" that the child can retreat to during times of anxiety

- making use of novelty and variety, and of drama and role play

- use of more complex language that "tends to feel more negotiative and may also intrigue the child" and also use of humour.

- working to build personal understanding and self-esteem in the child

- use of non-confrontational approaches

History

Newson first began to look at PDA as a specific syndrome in the 1980s when certain children referred to the Child Development Clinic at Nottingham University appeared to display and share many of the same characteristics. These children had often been referred because they seemed to show many autistic traits but were not typical in their presentation like those with classical autism or Asperger's syndrome. They had often been labelled as 'atypical autism' or PDD-NOS. Both of these terms were felt by parents to be unhelpful. She wrote up her findings in several papers based on increasingly larger groups of children. In 2003 this culminated in a proposal published in "Archives of Diseases in Childhood" for PDA to be recognised as a separate syndrome within the pervasive developmental disorders.