The aim of the full diagnostic  assessment process is to provide a definitive diagnostic opinion about the presence or otherwise of an Autistic Spectrum Disorder (ASD). During the assessment, other difficulties may be identified and further assessment recommended. For example, other overlapping neuro-developmental conditions such as ADHD might require diagnosis; and sensory or motor skills difficulties may need an Occupational Therapy assessment; or learning/educational difficulties may need an Educational Psychology assessment.

The Healthcare On Demand team will normally assess children from the age of 5 years old.

For those who are younger than this, a preliminary discussion is offered, and it may be that an alternative paediatric opinion is recommended.

The “gold standard” approach to the assessment of ASCs places an emphasis on multi-professional input, but in practice this is often difficult to arrange even within established NHS services. As a consequence, diagnoses are often made by professionals in isolation, or are not made at all.

Healthcare On Demand (HoD) offers a comprehensive assessment service for children and young people where there are queries around Autism Spectrum Conditions (ASCs) and, where required, involves other highly qualified HoD professionals alongside the lead clinician to contribute to the assessment.

This broad range of experience means that we are able to provide a combination of clinical and educational assessments that highlight a person’s strengths as well as difficulties.

Our practice complies with the standards Autism assessment for children and young people produced by the National Institute for Health and Care Excellence.

To see this document, please click HERE.

We accept referrals from GPs, other healthcare professionals, also individuals and families may self refer, if wished. Our preference is always to work in close collaboration with GPs and others, as this is the best practice, and is the approach most likely to ensure you get optimal care.

Please consider seeking a referral from your GP to the HoD clinic, if at all possible. It is in your best interests to do so, however we will not turn you away if this is not possible, for whatever reason. The practitioner(s) you consult may well seek your consent to keeping your GP informed of any diagnoses or treatment being undertaken, whether you enter the service via a GP or self referral.

Options for Autism Assessment – Specifically for Children and Young People

Healthcare on Demand is committed to ensuring that individuals and families do not pay for services that they do not need, or that they could access freely from the NHS. Following the preliminary screening, clinician recommendations can be provided via the Clinic Coordinator. Therefore, you will receive appropriate guidance on the correct next steps for you.

Step 1: Preliminary Screening

If you are not sure what you are looking for, or even whether an autism/ASCs assessment is indicated, you may request a preliminary screening step, at a modest cost, before deciding whether to proceed with a full assessment.

We accept referrals from GPs, other healthcare professionals, also parents and families may self-refer, as wished. However, we always encourage families to involve thier family doctor at the outset wherever possible.

Immediately Prior to, and During the Assessment

Information is gathered from parents and/or carers and others who know the child using a range of standard clinical tools/questionnaires, and information is elicited from the school where appropriate.

Some forms will need to be completed and returned to the Clinic Coordinator prior to the appointment.

The Assistant Psychologist will review the material provided and invite you to attend a face-to-face consultation. This may include using some other assessment tools, not already sent out before the meeting.

The whole range of measures used to screen, both before and during the screening appointment is likely to include:

  • Parental questionnaire including an abbreviated Developmental History Questionnaire
  • SDQ (Strengths and Difficulties Questionnaire, age specific version)
  • AQ-Child orAQ-Adol, depending on age. These are 50-item Autism Quotient assessment tools. If the child scores 76 out of 150 or more or the adolescent scores 30 out of 50 or more, or autism is suspected (based on clinical judgement and any past history as provided by an informant plus results of the SDQ), a comprehensive assessment for autism would be appropriate.
  • Social Communication Questionnaire. This is a 40-item parent report questionnaire and gives a score out of 40; a child must score above 15 in order for us to recommend proceeding with a full diagnostic  assessment – Step 2.
  • Questionnaires and rating scales from other settings – usually school (or college, where applicable)

What Happens During the Step 1 Consultation

  • The consultation will include a discussion on the difficulties that make you or your child think an autistic spectrum condition may be present, including anything in the history that may be significant. The family history may also be thought to be relevant, as will your education and history and information provided by the school/other educational environment.
  • The Assistant Psychologist will have a general discussion with you as a parent, and the child, in an age appropriate way. He/she will summarise the nature and range of difficulties experienced.
  • The questionnaire will also be reviewed or administered, as appropriate and can be scored during the consultation to give you a preliminary indication of potential findings.
  • After the session, the Assistant Psychologist will write up the report, including all items addressed plus the formal SCQ, AQ and SDQ results, and will give recommendations as to whether you should consider progressing to a full autism assessment.
  • Whereor autism is suspected (based on clinical judgement and any past history as provided by an informant, plus test results), a comprehensive assessment for autism would be appropriate.

If there is a low score and few other indicators of autism, then it is much less likely that the criteria for a diagnosis of autism/ASCs can be met, and so no further ASC-related assessments would be indicated.

The cost for Option 1 – Screening Consultation for children/adolescents, including written report provision is £250.

Screenings will be conducted by Natalie Bidad in association with Margot Heurtematte. You can learn more about Natalie by clicking on her picture below:

It is important to note that the screening step provides important indicators for your consideration, but it is not in itself the full diagnostic process. It gives you an indication of whether it is likely that you may meet the thresholds for diagnosis. You need to progress to Step 2 – if appropriate and wished – to establish a full, positive diagnosis.

It is in Step 2, a longer, more detailed and complex set of assessments with two practitioners from different disciplines that the firm diagnosis is established, and further recommendations on treatment and other forms of support can be made. Please note, if you do go on to Step 2, this is may well require the completion of further forms by you and your child’s school, in order to gain the optimum insights and a solid basis for a diagnostic decision.

Step 2: Full Diagnostic Assessment

If you have undertaken the screening process, and have been advised, or decided independently that you wish to proceed with a full assessment for potential Autism Spectrum Conditions, the process is as shown below:

What Happens During a full Diagnostic Assessment?

A full ASCs assessment is made up of several elements including:

General Developmental Assessment

General Developmental Assessment (GDA) is a broad-based clinical interview focusing on the person’s birth history, infancy and development through childhood. Whilst it has a focus on the areas most affected by Autism Spectrum Conditions and is conducted by professionals experienced in that field, the interview is not a standardised diagnostic assessment and as such can provide slightly less robust information. That said, a good GDA can be more robust that a standardised interview interpreted by an inexperienced clinician.

range of tests and assessments may be used, depending on the individual’s needs, and the assessment option selected.

If you have already been through Step 1, please be prepared to complete further questionnaires for this next set of diagnostic investigations. This may be requested of you and your child’s school.

These are carried out by TWO practitioners drawn from different disciplines.

The  disciplines who are able to establish a definitive Autism Spectrum Condition are:

Consultant Psychiatrists (in this setting, Child and Adolescent Psychiatrists)

Clinical (Child) Psychologists

Specialist (Child) Speech and Language Therapist, trained in autism assessments.

The clinicians will discuss your child’s needs and your concerns with you. They will carry out semi-structured play and assessment activities designed to evaluate your child’s physical, cognitive, speech/language and social development, alongside any potential medical needs.

These will include:

Structured Parent Interview (ADI-R)

This is a structured interview conducted by a Consultant Child and Adolescent Psychiatrist with the parents/carers of individuals who have been referred for the evaluation of possible Autism Spectrum Conditions. This interview is used for diagnostic purposes and measures behaviour in the areas of reciprocal social interaction, communication and language, and patterns of behaviour. The interview covers the referred individual’s full developmental history, and generally takes one to two hours. The caregivers are asked questions, spanning the three main behavioural areas, about either the individual’s current behaviour or behaviour at a certain point in time. Your child is not required to attend this appointment.

You may also be asked by the doctor to complete a Child Communication Checklist – 2,  also referred to as CCC 2. This is a document which is completed by both the parents and school, and may  be required to build a more complete clinical picture, especially if you do not opt to undertake the Step 1 screening phase.

Autism Diagnostic Observation Schedule – Second Edition (ADOS-2)

The ADOS-2 is administered by a specialist Speech and Language Therapist.

The assessment involves observing your child engaging in various assessment tasks with the Speech and Language Therapist. This may include a school visit, where deemed appropriate. These are standardised activities that allow the examiner to observe the occurrence or non-occurrence of behaviours that have been identified as important to the diagnosis of autism and other pervasive developmental disorders across developmental levels and chronological ages. The Speech and Language Therapist will score the ADOS-2 and feed these results back to the Consultant Psychiatrist.

The key elements of evidence are then brought together by the clinic coordinator including supplemental questionnaires (parents and school) and school feedback

It is best practice to carry out the ADOS and ADI assessments in the same week. The practitioners will then write up their two parallel reports, discuss the result, then you will have a feedback consultation within two weeks.

Your Report

All assessments culminate in the production of a detailed report, outlining the information gathered and explaining the conclusions that have been drawn. Where possible, alternative explanations for a person’s difficulties will be provided where an Autistic Spectrum Disorder is not identified.

The final report will also contain recommendations for home and education environments where appropriate.


The costs for Step 2, Full Diagnostic Assessment is made up of 2 parts:

  • Medical Assessment and report – £950
  • ADOS Assessment and report – £375

Total £1325, payable to the relvant practitioners

How Do I Book an Assessment?

You request an appointment directly with the practitioners you would like to consult.

You can choose from:

ONE of the Consultant Child and Adolescent Psychiatrists who provide the ADI-R assessment, as part of the diagnostic process:

PLUS – A Specialist Speech and Language Therapist ( for the ADOS section):

Just click on the clinicians’ names to be taken to their profile pages, where you can see their qualifications, experience and can even book an appointment by clicking on the Request an Appointment button  (the green button below the individual practitioner’s photograph).

The practitioner will then contact you to discuss any questions you may have, prior to the assessment consultation.

What Happens After The Assessment?
A detailed report will be prepared summarising the child’s developmental history and describing their current presentation in each of the key ASCs areas, along with the diagnostic conclusion and any recommendations for treatment/management and further assessment.

For some children and young people, with a more complex presentation, additional assessments may be recommended.

This may include optional additional assessments, at additional cost, of:

Cognitive Assessment

For some individuals, a cognitive assessment may be helpful.

The assessment typically consists of a series of tasks designed to establish a person’s level of ability in certain key areas including working memory, speed of mental processing, visuo-spatial skills and the understanding and use of language. These assessments are ‘standardised’ – they have been developed through extensive research and allow the examiner to compare a person’s scores against the average that would be expected for their age group.

These assessments are used to help establish whether underlying difficulties in one or more key area of cognitive functioning could be influencing a person’s difficulties in everyday life. They can also be used to identify educational/ employment difficulties, and subsequently allow professionals to make recommendations to schools and other educational establishments or employers regarding the individual.

In terms of ASD, cognitive assessments can identify patterns that are typically seen in people with these difficulties. They can also identify cognitive issues that may lead to patterns of functioning similar to ASD.

Education Assessment

ASCs can be pervasive disorders – a child’s difficulties would be evident across all settings, although they may vary a little in intensity and the extent to which they impact on successful functioning. A school, college or workplace assessment can be invaluable in confirming a diagnosis, or by highlighting inconsistencies that then inform an alternative formulation of a person’s underlying difficulties.

Interested in exploring the Assessment Options further? Please contact us by emailing