What happens during an ADHD or autism assessment?

An ADHD or autism assessment is not one universal test. One service may use several appointments with a multidisciplinary team; another may gather forms, history and clinical observation in a different sequence. The child may meet one professional or several.

The consistent principle is that diagnosis should come from the whole clinical assessment, not a single score or a short performance in one room.

Before the first appointment

The service may request referral information, school or nursery reports, questionnaires, health records and developmental history. Ask what must be returned, by whom and by when. Keep a copy.

Tell the team about access needs:

• preferred communication and processing time;
• sensory, mobility or personal-care needs;
• interpreter or communication support;
• anxiety about unfamiliar people or settings;
• medication timing, eating or health needs;
• whether remote or in-person appointments create particular barriers.

An adjustment helps the team see and hear the child more accurately. It is not special treatment designed to alter the result.

Ask what will happen to forms that arrive late and whether the assessment can proceed without every requested source. A long pathway may contain both administrative and clinical stages; not every delay has the same effect. Keep acknowledgement messages and tell the team if the child's school or contact details change.

Developmental and clinical history

A clinician will usually ask about early development and the child's current life. Topics may include pregnancy and birth where relevant, language, movement, play, learning, attention, relationships, sensory experience, sleep, eating, health, mental health and family history.

They are looking for pattern, onset, persistence, context, impact and other possible explanations. Say when you do not know or remember. Approximate information labelled as approximate is better than a confident invention.

The developmental history guide shows how to prepare without turning childhood into a diagnostic checklist.

The child's account

The team should seek the child's perspective in a form suitable for their age and communication. They may ask what is easy or hard, what other people misunderstand, what school feels like and what the child wants help with.

A child may speak differently with a clinician, use writing or need a parent present for some or all of the conversation. Ask how confidentiality works and what will be shared. Do not answer every question for the child, but do not require unsupported speech as the price of participation.

If the child says something that differs from your account, let both stand. The clinician's work is to understand the difference.

Consent, privacy and participation

Ask the team how it handles parental consent, the child's agreement or consent, confidentiality and information sharing. The answer will depend on the child's age, understanding, the task and the law where care is provided.

Clarify which conversations happen with parents, child and school, and what each person will later see in the report. A teenager may want time alone with the clinician; a younger child may need a parent to support communication. Neither arrangement should be assumed in advance.

If there are separated parents, care arrangements or safeguarding concerns, tell the service early and ask for its process. Do not use the assessment appointment to resolve a family dispute about facts or contact.

More than one appointment

Assessment can unfold over weeks or months. Keep a simple timeline of what each appointment contributed and what remains outstanding. Ask whether a later professional has access to earlier notes or needs the family to repeat information.

Tell the team about material changes between appointments: new medication, school move, health diagnosis, substantial loss of functioning or a different informant. Date the update. Avoid sending a continuous stream of minor events that obscures the assessment question.

If your child cannot participate in one part, ask whether the team has enough alternative information, needs a different format or will rearrange. Incomplete activity does not by itself decide the diagnosis.

Information from school or nursery

School information may describe learning, attention, communication, social participation, behaviour, support and variation across the day. The NHS says an ADHD specialist will usually contact the SENCO or teacher ^[3]. NHS autism information says teams may read school reports, speak to teachers or visit school ^[4].

NICE autism guidance recommends seeking a preschool or school report once assessment is agreed and considering observation in another setting when accounts and clinic findings differ ^[2].

Education staff do not need to endorse a diagnosis. They need to provide specific, balanced observations. The school information guide gives examples.

Questionnaires and rating scales

Parents, teachers and children may complete structured questionnaires. These compare reported features or impact using a consistent format. They can highlight areas for discussion and differences between raters.

They are not pass-or-fail diagnostic tests. NICE states that ADHD diagnosis should not be based solely on rating scales or observational data ^[1]. NICE also says autism-specific tools should not be relied on alone ^[2].

Answer from the period and context requested. Use comment boxes for variation, support and uncertainty. Do not coordinate answers between home and school to achieve agreement.

Observation and structured activities

The child may be observed talking, playing, solving tasks or responding to structured social and communication activities. An ADHD pathway may include a computer-based attention or activity task. NHS information describes such tests as something a specialist may use to help assess symptoms ^[3].

The task contributes information under those conditions. A child who enjoys it may focus differently from school. A child who becomes silent in clinic may communicate differently at home. Neither response proves or rules out a diagnosis.

Tell the team what is typical, what is unusual and what conditions were present. If the session was shortened, highly supported or affected by illness, record that.

Health and differential assessment

The team may review medical history, physical health, hearing, vision, sleep, mental health and other developmental or learning needs. Some services carry out a physical examination or arrange further assessment when indicated.

NICE ADHD guidance requires consideration of needs, coexisting conditions, social and educational circumstances and physical health ^[1]. NICE autism guidance lists possible differential and coexisting conditions and says the team should build a profile across learning, communication, motor, adaptive, mental-health, physical, sensory and social functioning ^[2].

This is why an assessment should not be reduced to proving a parent's first hypothesis. An alternative or additional finding may be clinically useful.

How the team reaches a conclusion

For ADHD, NICE says diagnosis should be made by a specialist psychiatrist, paediatrician or other appropriately qualified professional with relevant expertise. It uses full clinical and psychosocial assessment, developmental and psychiatric history, observer reports, mental-state assessment and impairment in two or more important settings ^[1].

For autism, NICE says clinicians should combine all sources with clinical judgement using recognised diagnostic criteria and should not rely on one autism tool ^[2]. The team may discuss the case together before feedback.

Possible conclusions include:

• diagnostic criteria are met;
• criteria are not met;
• another or coexisting condition needs assessment;
• uncertainty remains and more information or review is needed.

None should be inferred from the length of the appointment or how friendly, talkative or distressed the child appeared.

Ask whether the conclusion is made by one clinician or discussed by a team, and which professional holds responsibility for the final report. If professionals disagree, ask how the disagreement and uncertainty are handled. A multidisciplinary meeting is not evidence by itself; the useful question is which sources and clinical reasoning informed it.

If the team changes the assessment question during the pathway, it should explain why. For example, it may identify a language or health issue requiring another assessment. Ask whether the original question remains open and who coordinates the new route.

If accounts differ

Ask what the team thinks the discrepancy may mean and what evidence would clarify it. NICE autism guidance specifically advises gathering more information or observing another setting when reported signs and assessment observation differ ^[2].

Do not insist that difference proves masking. It may reflect support, structure, familiarity, task interest, misunderstanding, time, fatigue or another condition. Present examples of what the child does before, during and after demanding situations.

The Blog on masking during assessment helps frame this concern accurately.

Feedback and report

Ask when and how feedback will happen, whether your child can be involved separately and when the written report will arrive. The NHS says an autism report should explain what the team found, whether the person is autistic, strengths, support needs and other conditions identified ^[4]. NICE says autism findings and the basis of conclusions should be explained even when diagnosis is not reached ^[2].

At feedback, ask:

• What question did you assess?
• Which information did you use?
• What criteria were or were not met?
• What alternative or coexisting explanations did you consider?
• What remains uncertain?
• Which recommendations apply now?
• Who owns each next action?

The process should leave you with more than a label. It should explain the clinical reasoning and the child's current profile clearly enough to guide the next conversation.

Keep the report securely and read who it has been copied to. Ask how to request factual corrections and whom to contact if the document does not arrive. A verbal conclusion is important, but families, schools and future clinicians often need the written reasoning and recommendations.

Sources

1. NICE, Attention deficit hyperactivity disorder: diagnosis and management
2. NICE, Autism spectrum disorder in under 19s: recognition, referral and diagnosis
3. NHS, ADHD in children and young people
4. NHS, Autism assessments