Diagnosing PDA – children


A PDA (Pathological Demand Avoidance) profile of autism is usually identified during an ASD (Autism Spectrum Disorder) assessment.

Because there is still academic/clinical debate about the terminology/classification of PDA, recognition of PDA is currently inconsistent. Identifying PDA can also be tricky because it may present in ways that may be different to the way many people, including clinicians, currently think of autism and there are overlaps in presenting characteristics between a PDA profile of autism and other conditions.

However, the PDA profile can, and should, be taken into consideration when undertaking autism assessments. This is in accordance with NICE Guidelines, which list demand avoidance as a ‘symptom’ of autism. Autism assessments should consider all the presenting strengths and challenges, including demand avoidance. The extent of, and reasons for, demand avoidance should be determined in collaboration with the individual and, in children’s services, their parents. Demand avoidance can occur for different reasons, so it is important to understand that a PDA profile may not always be the explanation.

When assessing and diagnosing, clinicians can add appropriate descriptive terms to an ASD diagnosis. Supplementary terminology such as a ‘PDA profile’ or ‘characterised by extreme demand avoidance’ are widely used. This type of signposting is important as it highlights the need for the use of helpful approaches by professionals and families.

Clinicians can use their own clinical judgement to describe an individual child’s presentation of ASD and remain within the guidelines of the diagnostic manuals. The National Autistic Society has produced useful information that describes autism profiles and diagnostic criteria in more detail.

This page is designed to guide you through the diagnostic pathway for children in the UK and the various options available to families. Please see separate information on the Diagnostic Pathway for Adults.

What is the purpose of a diagnosis?

The purpose of a diagnosis is to help make better sense of a child’s strengths and challenges. This helps to provide everyone with a shared and accurate understanding of what approaches will be most helpful.

  • It highlights that a child’s difficulties are primarily due to a neuro-developmental condition, and are not due to ‘naughtiness’ or ‘poor parenting’
  • It can help children and families understand why certain difficulties are experienced and what can be done to help
  • It provides access to suitable services and support
  • It enables support at school to be tailored to meet a child’s specific needs, which may help with attendance issues and reduce exclusions

Some families decide not to seek a diagnosis, as they feel that knowing themselves what their child’s strengths and difficulties are is sufficient for them – it’s a personal choice for each family to make.

Collating evidence

Before starting the diagnostic process, it’s helpful to collate and organise your evidence. This can help you feel more confident when requesting a referral for assessment and provides medical professionals with clear explanations for your concerns. Your evidence should be clear, informative and to-the-point – these tips may help:

  • Firstly, list the autistic traits that your child presents with. The National Institute of Care and Excellence (NICE) provides a useful checklist for identifying possible autism spectrum disorder in under 19s here. Demand avoidant behaviour is listed as a sign and symptom under the ‘Responding to Others’ section.
  • Print off information about the PDA profile of autism and provide a brief summary of how you feel your child fits the key features
  • Provide evidence from someone else who can support your descriptions of your child’s difficulties. This person could be an extended family member, friend, teacher or an out of school activity leader.
  • Keep a diary about your child’s difficulties to give an overview of a typical week or month. Note down what happened in the lead up to the difficulty, how you dealt with the situation and what the outcome was (this helpful guide may be useful).
  • Provide any information or reports from previous assessments and document any conditions your child has been diagnosed with or treated for.
  • Make duplicates of your information so that you have a file to keep for your own records and one that you can share with professionals.

Diagnostic pathways

There are three diagnostic pathways: your local NHS pathway, a referral to an NHS specialist or independent diagnostic centre, and private assessments. Each is explained in more detail below.

1. Local NHS pathway

Some NHS autism diagnostic teams are experienced in recognising a PDA profile of ASD (please remember that diagnostic terminology may vary and that demand avoidance may occur for different reasons).

  1. Make an appointment with your GP to say that you think your child may be autistic. Submit the information that you’ve collated along with a letter requesting that your child is referred for an assessment. The pathway varies regionally but may include a referral to a Paediatrician, Child and Mental Health Service (CAMHS) or a Child Development Centre (CDC).
  2. If your referral is accepted you may need to attend further appointments to help the professionals involved to determine if onward referral to the ASD diagnostic team is appropriate. It’s during this stage of the process that you may face some obstacles if your local services aren’t experienced in the PDA profile of ASD – for more info please see Identifying PDA  and you may need to redirect everyone involved to the information you provided at the start of the process. This stage can be time consuming and involve numerous appointments.
  3. If your request for a referral is refused, ask to be provided in writing with the reasons why your child did not meet the criteria for onward referral. Understanding the exact reasons why your referral has been refused can help you to prepare a case for the decision to be reconsidered as detailed at the end of this page.
  4. NICE provides further information regarding the recommended pathway for local services to follow for each stage of the assessment and referral pathway, which you can download from their website: Autism spectrum disorder in under 19s: recognition, referral and diagnosis

2. Referral to NHS specialist or Independent Diagnostic Centre

Some NHS autism diagnostic teams may agree that they don’t have the necessary experience/expertise to assess. You can request onward referral to an NHS specialist in the field – this is assessed on need and accessed via your GP. You can also request a referral to an independent diagnostic centre – this may involve your GP submitting an Individual Funding Request to the Clinical Commissioning Group (CCG). It is important to discuss these options with your GP to ensure that you follow the correct local pathway to secure any funding that may be required. It can sometimes be helpful if your local MP is able to support this request. If the request is refused you can usually appeal this decision or make a complaint, but you would need to seek further information about the process for appeal from your local health authority, as this varies according to local policies.

3. Private assessments

Some parents decide on a private assessment from the outset, others may choose this option if they’ve been unable to make progress via the NHS pathway. Either way, it is still advisable to request a referral letter from your GP.

Sometimes parents are concerned that private assessments/diagnoses may not be accepted by local authorities, but provided the assessment has been conducted in accordance with NICE guidelines (i.e. by a multidisciplinary team) there should be very few grounds for local services not to accept the outcomes of a private assessment. If you encounter this problem, it can be helpful to ask the diagnosing clinician to contact the services on your behalf.

The independent autism diagnostic centres listed here all assess for Autism Spectrum Condition (ASC) and within that give consideration to the demand avoidant profile in accordance with NICE guidance. These services can be commissioned privately or by your Clinical Commissioning Group if they have approved funding for an assessment (see point 2 above). Costs can vary between £2,000 and £4,500 – please contact these centres directly for further information regarding costs, waiting times and their referral process. Please note that whilst the PDA Society researches all the services we signpost, the list should be taken as a helpful guide not as an endorsement and we can take no responsibility for the quality or the outcomes of assessments.

The autism diagnostic assessment

Once your child has been referred to the ASD diagnostic team, this service will decide whether they feel it is appropriate for them to carry out an assessment for ASD and/or an alternative assessment. This process should begin within 3 months from the referral.

ASD assessments should follow a similar process whether it is being conducted by the NHS or an independent diagnostic centre. The assessment should be conducted by a multi-disciplinary team, consisting of at least two professionals from different fields of expertise. The assessment should include:

  • A detailed history from parents or carers (this is usually gathered using an autism specific interview/diagnostic tool such as the Autism Diagnostic Interview-Revised (ADIR) or the Diagnostic Interview for Social and Communication Disorders (DISCO))
  • Direct observation of the child (this is usually performed during an Autism Diagnostic Observation Schedule (ADOS) assessment)
  • Observation in a different setting (services may gather reports from other settings for this purpose when this isn’t possible)
  • A general physical health check (if this hasn’t previously been conducted)
  • Reports from other professionals and agencies involved with the child

Autism spectrum disorder in under 19s: recognition, referral and diagnosis | Guidance | NICE and the National Autistic Society provide further information about what a diagnostic assessment should involve, and the PDA Development Group had produced a guide to what makes a good diagnostic assessment for a child with a PDA profile.

Outcomes of the assessment

Following an assessment, the diagnostician will tell you whether or not they think your child is on the autism spectrum. They might do this on the day of the assessment, by phone on a later date, or in a written report that they send to you in the post.

The report should give a clear diagnosis and a clear description of the child’s individual profile of strengths and needs. If the assessment team has concluded that your child does fit the PDA profile, the diagnosis may not state this explicitly. Different terminology is used from area to area and from clinician to clinician, some may refer to ‘Autism with a PDA profile/ASD with PDA traits’, others may give an ASD diagnosis and refer to demand avoidance in the accompanying report. The most important point is that demand avoidance is highlighted as being a key characteristic for your child as a signpost to helpful approaches.

If you don’t agree with the outcomes of the assessment

If you feel that your child’s presentation is complex, you can discuss this with the professional or team who conducted the assessment and request that your child is referred to a tertiary level service (a specialist level of health care). You can also seek a second opinion, by going back to the GP to explain that you aren’t happy with the diagnosis and ask the GP to refer your child elsewhere.

If any of the following apply after assessment, consider obtaining a second opinion (including referral to a specialised tertiary autism team if necessary):

  • Continued uncertainty about the diagnosis
  • Disagreement about the diagnosis within the autism team
  • Disagreement with parents or carers, or if appropriate the child or young person, about the diagnosis.
  • A lack of local access to particular skills and competencies needed to reach a diagnosis in a child or young person who has a complex coexisting condition.
  • A lack of response as expected to any therapeutic interventions provided to the child or young person.

Recommendations | Autism spectrum disorder in under 19s: recognition, referral and diagnosis | Guidance | NICE – point 1.6.2 (After the autism diagnostic assessment)

However, please note that funding issues can often delay or prevent the process of getting a second opinion and there may be no tertiary service in your local area.

What you can do if you are not satisfied at any stage of the process

  • Firstly try to resolve any issues directly with the service involved, providing your feedback or concerns in writing – this helpful toolkit from Cerebra gives some good tips
  • If this doesn’t resolve the issue, you can make a complaint
  • Sometimes it can be helpful to explain the situation to your MP who may be able to support you
  • Some families commission the services of a specialist solicitor, but this can be very expensive unless you qualify for legal aid
  • If you have a complaint about a private diagnostician they should have their own complaints procedure, as required by the Care Standards Act 2000.